CVE-2026-68136

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-68136", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.370Z", "datePublished": "2026-08-10T11:58:59.450Z", "dateUpdated": "2026-10-19T20:58:52.839Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-23T12:45:54.689Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: gro: fix double aggregation of flush-marked skbs\n\nCommit 0ab03f353d36 (\"net-gro: Fix GRO flush when receiving a GSO\npacket.\") added a flush check to skb_gro_receive(), but\nskb_gro_receive_list() lacks the same validation.\n\nAs a result, packets marked with NAPI_GRO_CB(skb)->flush may still be\nre-aggregated.\n\nThis allows already-GRO'd packets with existing frag_list to be\nre-aggregated into a new GRO session, corrupting the frag_list chain\nstructure. When skb_segment() attempts to unpack these malformed packets,\nit encounters invalid state and triggers a kernel panic.\n\nScenario (Tethering/Device forwarding):\n 1. Driver: Generated aggregated packet P1 via LRO with frag_list\n 2. Dev A: Receives aggregated fraglist packet and flush flag set\n 3. Dev A: Re-enters GRO, skb_gro_receive_list() is called\n 4. Missing flush check allows re-aggregation despite flush flag\n 5. Frag_list chain becomes corrupted (loops or dangling refs)\n 6. Dev B: TX path calls skb_segment(), crashes on corrupted frag_list\n\nRoot cause in skb_segment():\n The check at line ~4891:\n if (hsize <= 0 && i >= nfrags && skb_headlen(list_skb) &&\n (skb_headlen(list_skb) == len || sg)) {\n\n When frag_list is corrupted by double aggregation, when list_skb is\n a NULL pointer from skb->next, skb_headlen(list_skb) dereference\n NULL/corrupted pointers occurs.\n\nCall Trace:\n skb_headlen(NULL skb)\n skb_segment\n tcp_gso_segment\n tcp4_gso_segment\n inet_gso_segment\n skb_mac_gso_segment\n __skb_gso_segment\n skb_gso_segment\n validate_xmit_skb\n validate_xmit_skb_list\n sch_direct_xmit\n qdisc_restart\n __qdisc_run\n qdisc_run\n net_tx_action\n\nFix: Add NAPI_GRO_CB(skb)->flush validation to the early-return check in\nskb_gro_receive_list(), matching the defensive programming pattern of\nskb_gro_receive()."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL"}, "scenarios": [{"lang": "en", "value": "AV:N - The bug is reached from the standard NAPI GRO receive path processing remotely originated TCP/IP packets (napi_gro_receive\u2192dev_gro_receive\u2192tcp_gro_receive\u2192skb_gro_receive_list), including tethering/NAT/forwarding scenarios where packets re-enter GRO on a second netdev after driver LRO or prior GRO aggregation.\nAC:L - An attacker can reliably trigger the bug by crafting a TCP stream through a forwarding host with rx-gro-list enabled, without races or victim-specific timing; the commit documents a deterministic tethering/forwarding repro where flush-marked frag_list skbs are re-aggregated and later crash skb_segment.\nPR:N - No local privileges or authentication are required; any remote peer that can send TCP traffic through a vulnerable forwarding/tethering/NAT Linux host can reach the GRO fraglist merge path, which performs no capability or credential checks on the receive path.\nUI:N - Exploitation requires only network-delivered packets and normal kernel forwarding/GRO processing; the victim does not need to open files, mount filesystems, click links, or perform any deliberate action beyond routine network operation.\nS:U - Impact is confined to kernel memory corruption and panic within the same host kernel security domain during packet GRO aggregation and subsequent segmentation on transmit; it does not cross VM, container, or IOMMU boundaries to affect a separate security authority.\nC:H - Double aggregation corrupts the skb frag_list chain (loops, dangling references, NULL/corrupted list_skb pointers), constituting kernel heap memory corruption that can be read during skb_segment processing and is classifiable as a high-impact info-disclosure primitive beyond a simple crash.\nI:H - Re-aggregating flush-marked skbs with existing frag_list corrupts skb linked-list structure and reference relationships in kernel memory, enabling potential control of subsequent skb metadata and write/control-flow primitives during GSO segmentation, not merely integrity-preserving packet drops.\nA:H - Corrupted frag_list state causes skb_segment to dereference a NULL or invalid list_skb via skb_headlen(), producing a kernel panic/oops on the transmit path (sch_direct_xmit/qdisc_run), fully denying availability of the affected system."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/core/gro.c"], "versions": [{"version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "7fc7e35212cf58c134310fb47566a844297ceae9", "status": "affected", "versionType": "git"}, {"version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "d1fb23f8f794ac4683127bd49a6422bd87e0ac02", "status": "affected", "versionType": "git"}, {"version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "db3e82da616f52e2b27e25e7be3fde2f2a5e54d6", "status": "affected", "versionType": "git"}, {"version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "107e1a469f53a2a70874f3f12bf6fcd23925da1d", "status": "affected", "versionType": "git"}, {"version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "a4dfd46cc8f08a29c6183794790547d0945f3d45", "status": "affected", "versionType": "git"}, {"version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0", "status": "affected", "versionType": "git"}, {"version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "e751256486d0ded20f5a9f9863467f1dce65142f", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/core/gro.c"], "versions": [{"version": "5.6", "status": "affected"}, {"version": "0", "lessThan": "5.6", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.266", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.184", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.153", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.101", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.6", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "5.10.266"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "6.1.184"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "6.6.153"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "6.12.101"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "6.18.42"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "7.1.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/7fc7e35212cf58c134310fb47566a844297ceae9"}, {"url": "https://git.kernel.org/stable/c/d1fb23f8f794ac4683127bd49a6422bd87e0ac02"}, {"url": "https://git.kernel.org/stable/c/db3e82da616f52e2b27e25e7be3fde2f2a5e54d6"}, {"url": "https://git.kernel.org/stable/c/107e1a469f53a2a70874f3f12bf6fcd23925da1d"}, {"url": "https://git.kernel.org/stable/c/a4dfd46cc8f08a29c6183794790547d0945f3d45"}, {"url": "https://git.kernel.org/stable/c/fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0"}, {"url": "https://git.kernel.org/stable/c/e751256486d0ded20f5a9f9863467f1dce65142f"}], "title": "net: gro: fix double aggregation of flush-marked skbs", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-68136", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T15:44:29.127961Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-476", "description": "CWE-476 NULL Pointer Dereference"}]}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-19T20:58:52.839Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-68136", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T15:44:29.127961Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-476", "description": "CWE-476 NULL Pointer Dereference"}]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T15:44:29.680Z"}}], "cna": {"title": "net: gro: fix double aggregation of flush-marked skbs", "metrics": [{"cvssV3_1": {"version": "3.1", "baseScore": 9.8, "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}, "scenarios": [{"lang": "en", "value": "AV:N - The bug is reached from the standard NAPI GRO receive path processing remotely originated TCP/IP packets (napi_gro_receive\u2192dev_gro_receive\u2192tcp_gro_receive\u2192skb_gro_receive_list), including tethering/NAT/forwarding scenarios where packets re-enter GRO on a second netdev after driver LRO or prior GRO aggregation.\nAC:L - An attacker can reliably trigger the bug by crafting a TCP stream through a forwarding host with rx-gro-list enabled, without races or victim-specific timing; the commit documents a deterministic tethering/forwarding repro where flush-marked frag_list skbs are re-aggregated and later crash skb_segment.\nPR:N - No local privileges or authentication are required; any remote peer that can send TCP traffic through a vulnerable forwarding/tethering/NAT Linux host can reach the GRO fraglist merge path, which performs no capability or credential checks on the receive path.\nUI:N - Exploitation requires only network-delivered packets and normal kernel forwarding/GRO processing; the victim does not need to open files, mount filesystems, click links, or perform any deliberate action beyond routine network operation.\nS:U - Impact is confined to kernel memory corruption and panic within the same host kernel security domain during packet GRO aggregation and subsequent segmentation on transmit; it does not cross VM, container, or IOMMU boundaries to affect a separate security authority.\nC:H - Double aggregation corrupts the skb frag_list chain (loops, dangling references, NULL/corrupted list_skb pointers), constituting kernel heap memory corruption that can be read during skb_segment processing and is classifiable as a high-impact info-disclosure primitive beyond a simple crash.\nI:H - Re-aggregating flush-marked skbs with existing frag_list corrupts skb linked-list structure and reference relationships in kernel memory, enabling potential control of subsequent skb metadata and write/control-flow primitives during GSO segmentation, not merely integrity-preserving packet drops.\nA:H - Corrupted frag_list state causes skb_segment to dereference a NULL or invalid list_skb via skb_headlen(), producing a kernel panic/oops on the transmit path (sch_direct_xmit/qdisc_run), fully denying availability of the affected system."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "7fc7e35212cf58c134310fb47566a844297ceae9", "versionType": "git"}, {"status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "d1fb23f8f794ac4683127bd49a6422bd87e0ac02", "versionType": "git"}, {"status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "db3e82da616f52e2b27e25e7be3fde2f2a5e54d6", "versionType": "git"}, {"status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "107e1a469f53a2a70874f3f12bf6fcd23925da1d", "versionType": "git"}, {"status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "a4dfd46cc8f08a29c6183794790547d0945f3d45", "versionType": "git"}, {"status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0", "versionType": "git"}, {"status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "lessThan": "e751256486d0ded20f5a9f9863467f1dce65142f", "versionType": "git"}], "programFiles": ["net/core/gro.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.6"}, {"status": "unaffected", "version": "0", "lessThan": "5.6", "versionType": "semver"}, {"status": "unaffected", "version": "5.10.266", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "6.1.184", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.153", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.101", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.42", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.1.6", "versionType": "semver", "lessThanOrEqual": "7.1.*"}, {"status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/core/gro.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/7fc7e35212cf58c134310fb47566a844297ceae9"}, {"url": "https://git.kernel.org/stable/c/d1fb23f8f794ac4683127bd49a6422bd87e0ac02"}, {"url": "https://git.kernel.org/stable/c/db3e82da616f52e2b27e25e7be3fde2f2a5e54d6"}, {"url": "https://git.kernel.org/stable/c/107e1a469f53a2a70874f3f12bf6fcd23925da1d"}, {"url": "https://git.kernel.org/stable/c/a4dfd46cc8f08a29c6183794790547d0945f3d45"}, {"url": "https://git.kernel.org/stable/c/fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0"}, {"url": "https://git.kernel.org/stable/c/e751256486d0ded20f5a9f9863467f1dce65142f"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: gro: fix double aggregation of flush-marked skbs\n\nCommit 0ab03f353d36 (\"net-gro: Fix GRO flush when receiving a GSO\npacket.\") added a flush check to skb_gro_receive(), but\nskb_gro_receive_list() lacks the same validation.\n\nAs a result, packets marked with NAPI_GRO_CB(skb)->flush may still be\nre-aggregated.\n\nThis allows already-GRO'd packets with existing frag_list to be\nre-aggregated into a new GRO session, corrupting the frag_list chain\nstructure. When skb_segment() attempts to unpack these malformed packets,\nit encounters invalid state and triggers a kernel panic.\n\nScenario (Tethering/Device forwarding):\n 1. Driver: Generated aggregated packet P1 via LRO with frag_list\n 2. Dev A: Receives aggregated fraglist packet and flush flag set\n 3. Dev A: Re-enters GRO, skb_gro_receive_list() is called\n 4. Missing flush check allows re-aggregation despite flush flag\n 5. Frag_list chain becomes corrupted (loops or dangling refs)\n 6. Dev B: TX path calls skb_segment(), crashes on corrupted frag_list\n\nRoot cause in skb_segment():\n The check at line ~4891:\n if (hsize <= 0 && i >= nfrags && skb_headlen(list_skb) &&\n (skb_headlen(list_skb) == len || sg)) {\n\n When frag_list is corrupted by double aggregation, when list_skb is\n a NULL pointer from skb->next, skb_headlen(list_skb) dereference\n NULL/corrupted pointers occurs.\n\nCall Trace:\n skb_headlen(NULL skb)\n skb_segment\n tcp_gso_segment\n tcp4_gso_segment\n inet_gso_segment\n skb_mac_gso_segment\n __skb_gso_segment\n skb_gso_segment\n validate_xmit_skb\n validate_xmit_skb_list\n sch_direct_xmit\n qdisc_restart\n __qdisc_run\n qdisc_run\n net_tx_action\n\nFix: Add NAPI_GRO_CB(skb)->flush validation to the early-return check in\nskb_gro_receive_list(), matching the defensive programming pattern of\nskb_gro_receive()."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.266", "versionStartIncluding": "5.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.184", "versionStartIncluding": "5.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.153", "versionStartIncluding": "5.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.101", "versionStartIncluding": "5.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.18.42", "versionStartIncluding": "5.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.1.6", "versionStartIncluding": "5.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.2", "versionStartIncluding": "5.6"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-23T12:45:54.689Z"}}}, "cveMetadata": {"cveId": "CVE-2026-68136", "state": "PUBLISHED", "dateUpdated": "2026-10-19T20:58:52.839Z", "dateReserved": "2026-07-30T09:28:09.370Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2026-08-10T11:58:59.450Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/core/gro.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "7fc7e35212cf58c134310fb47566a844297ceae9", "status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "versionType": "git"}, {"lessThan": "d1fb23f8f794ac4683127bd49a6422bd87e0ac02", "status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "versionType": "git"}, {"lessThan": "db3e82da616f52e2b27e25e7be3fde2f2a5e54d6", "status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "versionType": "git"}, {"lessThan": "107e1a469f53a2a70874f3f12bf6fcd23925da1d", "status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "versionType": "git"}, {"lessThan": "a4dfd46cc8f08a29c6183794790547d0945f3d45", "status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "versionType": "git"}, {"lessThan": "fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0", "status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "versionType": "git"}, {"lessThan": "e751256486d0ded20f5a9f9863467f1dce65142f", "status": "affected", "version": "3a1296a38d0cf62bffb9a03c585cbd5dbf15d596", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/core/gro.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.6"}, {"lessThan": "5.6", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.266", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.184", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.153", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.101", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.42", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.6", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: gro: fix double aggregation of flush-marked skbs\n\nCommit 0ab03f353d36 (\"net-gro: Fix GRO flush when receiving a GSO\npacket.\") added a flush check to skb_gro_receive(), but\nskb_gro_receive_list() lacks the same validation.\n\nAs a result, packets marked with NAPI_GRO_CB(skb)->flush may still be\nre-aggregated.\n\nThis allows already-GRO'd packets with existing frag_list to be\nre-aggregated into a new GRO session, corrupting the frag_list chain\nstructure. When skb_segment() attempts to unpack these malformed packets,\nit encounters invalid state and triggers a kernel panic.\n\nScenario (Tethering/Device forwarding):\n 1. Driver: Generated aggregated packet P1 via LRO with frag_list\n 2. Dev A: Receives aggregated fraglist packet and flush flag set\n 3. Dev A: Re-enters GRO, skb_gro_receive_list() is called\n 4. Missing flush check allows re-aggregation despite flush flag\n 5. Frag_list chain becomes corrupted (loops or dangling refs)\n 6. Dev B: TX path calls skb_segment(), crashes on corrupted frag_list\n\nRoot cause in skb_segment():\n The check at line ~4891:\n if (hsize <= 0 && i >= nfrags && skb_headlen(list_skb) &&\n (skb_headlen(list_skb) == len || sg)) {\n\n When frag_list is corrupted by double aggregation, when list_skb is\n a NULL pointer from skb->next, skb_headlen(list_skb) dereference\n NULL/corrupted pointers occurs.\n\nCall Trace:\n skb_headlen(NULL skb)\n skb_segment\n tcp_gso_segment\n tcp4_gso_segment\n inet_gso_segment\n skb_mac_gso_segment\n __skb_gso_segment\n skb_gso_segment\n validate_xmit_skb\n validate_xmit_skb_list\n sch_direct_xmit\n qdisc_restart\n __qdisc_run\n qdisc_run\n net_tx_action\n\nFix: Add NAPI_GRO_CB(skb)->flush validation to the early-return check in\nskb_gro_receive_list(), matching the defensive programming pattern of\nskb_gro_receive()."}], "id": "CVE-2026-68136", "lastModified": "2026-10-19T21:17:53.333", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-68136", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-16T15:44:29.127961Z", "version": "2.0.3"}}]}, "published": "2026-08-10T13:19:59.120", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/107e1a469f53a2a70874f3f12bf6fcd23925da1d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7fc7e35212cf58c134310fb47566a844297ceae9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a4dfd46cc8f08a29c6183794790547d0945f3d45"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d1fb23f8f794ac4683127bd49a6422bd87e0ac02"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/db3e82da616f52e2b27e25e7be3fde2f2a5e54d6"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e751256486d0ded20f5a9f9863467f1dce65142f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-476"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "kernel: Linux kernel: Denial of Service in GRO due to double aggregation of network packets", "id": "2513163", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2513163"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.9", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-476", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nnet: gro: fix double aggregation of flush-marked skbs\nCommit 0ab03f353d36 (\"net-gro: Fix GRO flush when receiving a GSO\npacket.\") added a flush check to skb_gro_receive(), but\nskb_gro_receive_list() lacks the same validation.\nAs a result, packets marked with NAPI_GRO_CB(skb)->flush may still be\nre-aggregated.\nThis allows already-GRO'd packets with existing frag_list to be\nre-aggregated into a new GRO session, corrupting the frag_list chain\nstructure. When skb_segment() attempts to unpack these malformed packets,\nit encounters invalid state and triggers a kernel panic.\nScenario (Tethering/Device forwarding):\n1. Driver: Generated aggregated packet P1 via LRO with frag_list\n2. Dev A: Receives aggregated fraglist packet and flush flag set\n3. Dev A: Re-enters GRO, skb_gro_receive_list() is called\n4. Missing flush check allows re-aggregation despite flush flag\n5. Frag_list chain becomes corrupted (loops or dangling refs)\n6. Dev B: TX path calls skb_segment(), crashes on corrupted frag_list\nRoot cause in skb_segment():\nThe check at line ~4891:\nif (hsize <= 0 && i >= nfrags && skb_headlen(list_skb) &&\n(skb_headlen(list_skb) == len || sg)) {\nWhen frag_list is corrupted by double aggregation, when list_skb is\na NULL pointer from skb->next, skb_headlen(list_skb) dereference\nNULL/corrupted pointers occurs.\nCall Trace:\nskb_headlen(NULL skb)\nskb_segment\ntcp_gso_segment\ntcp4_gso_segment\ninet_gso_segment\nskb_mac_gso_segment\n__skb_gso_segment\nskb_gso_segment\nvalidate_xmit_skb\nvalidate_xmit_skb_list\nsch_direct_xmit\nqdisc_restart\n__qdisc_run\nqdisc_run\nnet_tx_action\nFix: Add NAPI_GRO_CB(skb)->flush validation to the early-return check in\nskb_gro_receive_list(), matching the defensive programming pattern of\nskb_gro_receive().", "A flaw was found in the Linux kernel's Generic Receive Offload (GRO) networking subsystem. An attacker could exploit this by sending specially crafted network packets that cause a double aggregation of flush-marked socket buffers (skbs). This issue arises from a missing flush check, which allows already-processed packets to be re-aggregated, corrupting the internal data structure. This corruption leads to an invalid state when the system attempts to process these packets, triggering a kernel panic and resulting in a Denial of Service (DoS)."], "name": "CVE-2026-68136", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:enterprise_linux_nvidia:", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux for NVIDIA 26"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "rhcos", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-08-10T11:58:59Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-68136\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-68136\nhttps://git.kernel.org/stable/c/107e1a469f53a2a70874f3f12bf6fcd23925da1d\nhttps://git.kernel.org/stable/c/a4dfd46cc8f08a29c6183794790547d0945f3d45\nhttps://git.kernel.org/stable/c/e751256486d0ded20f5a9f9863467f1dce65142f\nhttps://git.kernel.org/stable/c/fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[3a1296a38d0cf62bffb9a03c585cbd5dbf15d596,107e1a469f53a2a70874f3f12bf6fcd23925da1d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[3a1296a38d0cf62bffb9a03c585cbd5dbf15d596,a4dfd46cc8f08a29c6183794790547d0945f3d45)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[3a1296a38d0cf62bffb9a03c585cbd5dbf15d596,fc0c0f7a207f0cd2d2aa725696c907f7d03af9e0)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[3a1296a38d0cf62bffb9a03c585cbd5dbf15d596,e751256486d0ded20f5a9f9863467f1dce65142f)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "5.6"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,5.6)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.101,6.13.0]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.42,6.19.0]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.6,7.2.0]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-rc5,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-08-10T14:15:03.850883+00:00", "updated": "2026-08-14T00:00:04.158345+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}