CVE-2026-31700

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A concurrent\nuserspace thread can modify the vnet_hdr fields between validation\nand use, bypassing all safety checks.\n\nThe non-TPACKET path (packet_snd()) already correctly copies vnet_hdr\nto a stack-local variable. All other vnet_hdr consumers in the kernel\n(tun.c, tap.c, virtio_net.c) also use stack copies. The TPACKET TX\npath is the only caller of virtio_net_hdr_to_skb() that reads directly\nfrom user-controlled shared memory.\n\nFix this by copying vnet_hdr from the mmap'd ring buffer to a\nstack-local variable before validation and use, consistent with the\napproach used in packet_snd() and all other callers."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerable path is reached through local AF_PACKET socket operations, specifically configuring PACKET_VNET_HDR and PACKET_TX_RING, mmaping the TX ring, and calling sendmsg(). It is not reachable from unauthenticated remote network packets.\nAC:L - Although this is a race, the attacker controls both sides: one thread drives tpacket_snd() while another rewrites the mmap'd vnet_hdr in shared ring memory. Upstream discussion also confirmed practical race wins with a PoC, so no external condition makes exploitation high complexity.\nPR:L - Creating the AF_PACKET SOCK_RAW socket requires CAP_NET_RAW, but packet_create() checks ns_capable(net->user_ns, CAP_NET_RAW). This capability is obtainable by an unprivileged local user in a user/network namespace on systems allowing unprivileged user namespaces, so this is Low rather than High.\nUI:N - No victim action is needed after the attacker has local execution; the attacker configures the socket, maps the ring, races the header, and sends packets directly.\nS:U - The vulnerability is in the kernel networking stack and impacts the same kernel security authority. Even if exploited for local privilege escalation, this is standard kernel compromise rather than a cross-scope boundary such as guest-to-host escape.\nC:H - Racing the validated vnet_hdr can corrupt skb metadata and can make the kernel transmit or process data outside the validated packet contents, including potential kernel heap disclosure. Given the memory corruption and kernel data exposure potential, confidentiality impact is High.\nI:H - The race can bypass checksum and GSO validation for fields such as gso_type, gso_size, flags, csum_start, and csum_offset, enabling malicious skb state and kernel memory corruption. Upstream patch discussion explicitly identified potential local privilege escalation, so integrity impact is High.\nA:H - Invalid checksum/GSO metadata and corrupted skb state can trigger kernel warnings, BUG/Oops paths, or crashes in the transmit/GSO path. Repeated local triggering can therefore cause high availability impact."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/packet/af_packet.c"], "versions": [{"version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "0f4c9754956b86de158a4af5278c5cf5bda9439e", "status": "affected", "versionType": "git"}, {"version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "714aa973da8163925eda7efd49361ccbee21ee46", "status": "affected", "versionType": "git"}, {"version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "1490f82353bdabc09265a74e645b07f05cf4188e", "status": "affected", "versionType": "git"}, {"version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "74e2db36fe50e3ad9d5300d7fd0e6e2a15a6d121", "status": "affected", "versionType": "git"}, {"version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "3a1bf9116ea31470b89692585c3910dfe830dcdd", "status": "affected", "versionType": "git"}, {"version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "28324a3b62d9ce7f9bdd65a8ce63f382041d1b27", "status": "affected", "versionType": "git"}, {"version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "48a6ef291a17639e1b6ae0fbe9c8b2bb87d7804b", "status": "affected", "versionType": "git"}, {"version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "2c054e17d9d41f1020376806c7f750834ced4dc5", "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/packet/af_packet.c"], "versions": [{"version": "4.6", "status": "affected"}, {"version": "0", "lessThan": "4.6", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.259", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.210", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.176", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.136", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.84", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.25", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0.2", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1", "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": "4.6", "versionEndExcluding": "5.10.259"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6", "versionEndExcluding": "5.15.210"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6", "versionEndExcluding": "6.1.176"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6", "versionEndExcluding": "6.6.136"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6", "versionEndExcluding": "6.12.84"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6", "versionEndExcluding": "6.18.25"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6", "versionEndExcluding": "7.0.2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.6", "versionEndExcluding": "7.1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/0f4c9754956b86de158a4af5278c5cf5bda9439e"}, {"url": "https://git.kernel.org/stable/c/714aa973da8163925eda7efd49361ccbee21ee46"}, {"url": "https://git.kernel.org/stable/c/1490f82353bdabc09265a74e645b07f05cf4188e"}, {"url": "https://git.kernel.org/stable/c/74e2db36fe50e3ad9d5300d7fd0e6e2a15a6d121"}, {"url": "https://git.kernel.org/stable/c/3a1bf9116ea31470b89692585c3910dfe830dcdd"}, {"url": "https://git.kernel.org/stable/c/28324a3b62d9ce7f9bdd65a8ce63f382041d1b27"}, {"url": "https://git.kernel.org/stable/c/48a6ef291a17639e1b6ae0fbe9c8b2bb87d7804b"}, {"url": "https://git.kernel.org/stable/c/2c054e17d9d41f1020376806c7f750834ced4dc5"}], "title": "net/packet: fix TOCTOU race on mmap'd vnet_hdr in tpacket_snd()", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"x_adpType": "supplier", "providerMetadata": {"orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "shortName": "siemens-SADP", "dateUpdated": 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It is not reachable from unauthenticated remote network packets.\nAC:L - Although this is a race, the attacker controls both sides: one thread drives tpacket_snd() while another rewrites the mmap'd vnet_hdr in shared ring memory. Upstream discussion also confirmed practical race wins with a PoC, so no external condition makes exploitation high complexity.\nPR:L - Creating the AF_PACKET SOCK_RAW socket requires CAP_NET_RAW, but packet_create() checks ns_capable(net->user_ns, CAP_NET_RAW). This capability is obtainable by an unprivileged local user in a user/network namespace on systems allowing unprivileged user namespaces, so this is Low rather than High.\nUI:N - No victim action is needed after the attacker has local execution; the attacker configures the socket, maps the ring, races the header, and sends packets directly.\nS:U - The vulnerability is in the kernel networking stack and impacts the same kernel security authority. Even if exploited for local privilege escalation, this is standard kernel compromise rather than a cross-scope boundary such as guest-to-host escape.\nC:H - Racing the validated vnet_hdr can corrupt skb metadata and can make the kernel transmit or process data outside the validated packet contents, including potential kernel heap disclosure. Given the memory corruption and kernel data exposure potential, confidentiality impact is High.\nI:H - The race can bypass checksum and GSO validation for fields such as gso_type, gso_size, flags, csum_start, and csum_offset, enabling malicious skb state and kernel memory corruption. Upstream patch discussion explicitly identified potential local privilege escalation, so integrity impact is High.\nA:H - Invalid checksum/GSO metadata and corrupted skb state can trigger kernel warnings, BUG/Oops paths, or crashes in the transmit/GSO path. Repeated local triggering can therefore cause high availability impact."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "0f4c9754956b86de158a4af5278c5cf5bda9439e", "versionType": "git"}, {"status": "affected", "version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "714aa973da8163925eda7efd49361ccbee21ee46", "versionType": "git"}, {"status": "affected", "version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "1490f82353bdabc09265a74e645b07f05cf4188e", "versionType": "git"}, {"status": "affected", "version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "74e2db36fe50e3ad9d5300d7fd0e6e2a15a6d121", "versionType": "git"}, {"status": "affected", "version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "3a1bf9116ea31470b89692585c3910dfe830dcdd", "versionType": "git"}, {"status": "affected", "version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "28324a3b62d9ce7f9bdd65a8ce63f382041d1b27", "versionType": "git"}, {"status": "affected", "version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "48a6ef291a17639e1b6ae0fbe9c8b2bb87d7804b", "versionType": "git"}, {"status": "affected", "version": "1d036d25e5609ba73fee6a88db01c306b140d512", "lessThan": "2c054e17d9d41f1020376806c7f750834ced4dc5", "versionType": "git"}], "programFiles": ["net/packet/af_packet.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "4.6"}, {"status": "unaffected", "version": "0", "lessThan": "4.6", "versionType": "semver"}, {"status": "unaffected", "version": "5.10.259", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.210", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.176", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.136", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.84", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.25", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.0.2", "versionType": "semver", "lessThanOrEqual": "7.0.*"}, {"status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/packet/af_packet.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/0f4c9754956b86de158a4af5278c5cf5bda9439e"}, {"url": "https://git.kernel.org/stable/c/714aa973da8163925eda7efd49361ccbee21ee46"}, {"url": "https://git.kernel.org/stable/c/1490f82353bdabc09265a74e645b07f05cf4188e"}, {"url": "https://git.kernel.org/stable/c/74e2db36fe50e3ad9d5300d7fd0e6e2a15a6d121"}, {"url": "https://git.kernel.org/stable/c/3a1bf9116ea31470b89692585c3910dfe830dcdd"}, {"url": "https://git.kernel.org/stable/c/28324a3b62d9ce7f9bdd65a8ce63f382041d1b27"}, {"url": "https://git.kernel.org/stable/c/48a6ef291a17639e1b6ae0fbe9c8b2bb87d7804b"}, {"url": "https://git.kernel.org/stable/c/2c054e17d9d41f1020376806c7f750834ced4dc5"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/packet: fix TOCTOU race on mmap'd vnet_hdr in tpacket_snd()\n\nIn tpacket_snd(), when PACKET_VNET_HDR is enabled, vnet_hdr points\ndirectly into the mmap'd TX ring buffer shared with userspace. The\nkernel validates the header via __packet_snd_vnet_parse() but then\nre-reads all fields later in virtio_net_hdr_to_skb(). A concurrent\nuserspace thread can modify the vnet_hdr fields between validation\nand use, bypassing all safety checks.\n\nThe non-TPACKET path (packet_snd()) already correctly copies vnet_hdr\nto a stack-local variable. All other vnet_hdr consumers in the kernel\n(tun.c, tap.c, virtio_net.c) also use stack copies. The TPACKET TX\npath is the only caller of virtio_net_hdr_to_skb() that reads directly\nfrom user-controlled shared memory.\n\nFix this by copying vnet_hdr from the mmap'd ring buffer to a\nstack-local variable before validation and use, consistent with the\napproach used in packet_snd() and all other callers."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.259", "versionStartIncluding": "4.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15.210", "versionStartIncluding": "4.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.176", "versionStartIncluding": "4.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.136", "versionStartIncluding": "4.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.84", "versionStartIncluding": "4.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.18.25", "versionStartIncluding": "4.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.0.2", "versionStartIncluding": "4.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.1", "versionStartIncluding": "4.6"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:24:37.797Z"}}}, "cveMetadata": {"cveId": "CVE-2026-31700", "state": "PUBLISHED", "dateUpdated": "2026-11-10T12:45:34.144Z", "dateReserved": "2026-03-09T15:48:24.132Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2026-05-01T13:56:00.205Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

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GNU/Linux subsystem", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "0", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.6", "versionType": "custom"}]}, {"defaultStatus": "unknown", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "vendor": "Siemens", "versions": [{"lessThan": "*", "status": "affected", "version": "V3.1.7", "versionType": "custom"}]}], "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "7A6CE177-C7BA-4E34-9D61-035565B5FFF5", "versionEndExcluding": "6.6.136", "versionStartIncluding": "4.6", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "D4ECA0DE-AFF5-4688-B219-4CA2336CA5B7", "versionEndExcluding": "6.12.84", "versionStartIncluding": "6.7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "8B0A7E0E-F6D8-45DB-8CD9-01839FE40A6C", "versionEndExcluding": "6.18.25", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "1BD58F1E-7C20-4C0D-92A2-FAC5CBFBE8A8", "versionEndExcluding": "7.0.2", "versionStartIncluding": "6.19", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*", "matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*", "matchCriteriaId": "0D38F0BF-A728-4133-A358-D44A2F7EE6D6", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/packet: fix TOCTOU race on mmap'd vnet_hdr in tpacket_snd()\n\nIn tpacket_snd(), when PACKET_VNET_HDR is enabled, vnet_hdr points\ndirectly into the mmap'd TX ring buffer shared with userspace. The\nkernel validates the header via __packet_snd_vnet_parse() but then\nre-reads all fields later in virtio_net_hdr_to_skb(). A concurrent\nuserspace thread can modify the vnet_hdr fields between validation\nand use, bypassing all safety checks.\n\nThe non-TPACKET path (packet_snd()) already correctly copies vnet_hdr\nto a stack-local variable. All other vnet_hdr consumers in the kernel\n(tun.c, tap.c, virtio_net.c) also use stack copies. The TPACKET TX\npath is the only caller of virtio_net_hdr_to_skb() that reads directly\nfrom user-controlled shared memory.\n\nFix this by copying vnet_hdr from the mmap'd ring buffer to a\nstack-local variable before validation and use, consistent with the\napproach used in packet_snd() and all other callers."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet/packet: corregir la condici\u00f3n de carrera TOCTOU en vnet_hdr mapeado por mmap en tpacket_snd()\n\nEn tpacket_snd(), cuando PACKET_VNET_HDR est\u00e1 habilitado, vnet_hdr apunta directamente al b\u00fafer de anillo TX mapeado por mmap compartido con el espacio de usuario. El kernel valida el encabezado a trav\u00e9s de __packet_snd_vnet_parse() pero luego vuelve a leer todos los campos m\u00e1s tarde en virtio_net_hdr_to_skb(). Un hilo concurrente del espacio de usuario puede modificar los campos de vnet_hdr entre la validaci\u00f3n y el uso, eludiendo todas las comprobaciones de seguridad.\n\nLa ruta no-TPACKET (packet_snd()) ya copia correctamente vnet_hdr a una variable local de la pila. Todos los dem\u00e1s consumidores de vnet_hdr en el kernel (tun.c, tap.c, virtio_net.c) tambi\u00e9n usan copias en la pila. La ruta TPACKET TX es el \u00fanico llamador de virtio_net_hdr_to_skb() que lee directamente de memoria compartida controlada por el usuario.\n\nSolucione esto copiando vnet_hdr del b\u00fafer de anillo mapeado por mmap a una variable local de la pila antes de la validaci\u00f3n y el uso, consistente con el enfoque utilizado en packet_snd() y todos los dem\u00e1s llamadores."}], "id": "CVE-2026-31700", "lastModified": "2026-11-11T21:10:00.200", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-31700", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-16T15:12:43.080685Z", "version": "2.0.3"}}]}, "published": "2026-05-01T14:16:19.907", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/0f4c9754956b86de158a4af5278c5cf5bda9439e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/1490f82353bdabc09265a74e645b07f05cf4188e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/28324a3b62d9ce7f9bdd65a8ce63f382041d1b27"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2c054e17d9d41f1020376806c7f750834ced4dc5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/3a1bf9116ea31470b89692585c3910dfe830dcdd"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/48a6ef291a17639e1b6ae0fbe9c8b2bb87d7804b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/714aa973da8163925eda7efd49361ccbee21ee46"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/74e2db36fe50e3ad9d5300d7fd0e6e2a15a6d121"}, {"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"}, {"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "url": "https://cert-portal.siemens.com/productcert/html/ssa-457936.html"}, {"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "url": "https://cert-portal.siemens.com/productcert/html/ssa-784472.html"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-362"}], "source": "nvd@nist.gov", "type": "Primary"}, {"description": [{"lang": "en", "value": "CWE-367"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "kernel: net/packet: fix TOCTOU race on mmap'd vnet_hdr in tpacket_snd()", "id": "2464358", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2464358"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-367", "details": ["A flaw was found in the Linux kernel. A Time-of-check to Time-of-use (TOCTOU) race condition exists in the `tpacket_snd()` function when `PACKET_VNET_HDR` is enabled. A local user can exploit this by modifying the `vnet_hdr` fields in the mmap'd TX ring buffer between validation and use, thereby bypassing safety checks. This could allow a local attacker to achieve a security bypass."], "name": "CVE-2026-31700", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "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": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-05-01T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-31700\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31700\nhttps://lore.kernel.org/linux-cve-announce/2026050119-CVE-2026-31700-c820@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1d036d25e5609ba73fee6a88db01c306b140d512,74e2db36fe50e3ad9d5300d7fd0e6e2a15a6d121)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1d036d25e5609ba73fee6a88db01c306b140d512,3a1bf9116ea31470b89692585c3910dfe830dcdd)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1d036d25e5609ba73fee6a88db01c306b140d512,28324a3b62d9ce7f9bdd65a8ce63f382041d1b27)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1d036d25e5609ba73fee6a88db01c306b140d512,48a6ef291a17639e1b6ae0fbe9c8b2bb87d7804b)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1d036d25e5609ba73fee6a88db01c306b140d512,2c054e17d9d41f1020376806c7f750834ced4dc5)"}}], "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": "semver", "value": "4.6"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,4.6)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.136,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.84,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.25,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.0.2,8.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1-rc1,*]"}}], "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": "2026-05-01T21:45:09.326500+00:00", "updated": "2026-05-06T22:00:14.067592+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}