CVE-2026-98525

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98525", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.355Z", "datePublished": "2026-10-18T15:17:43.216Z", "dateUpdated": "2026-10-19T09:21:07.010Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:21:07.010Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmctp: route: iterate socket tag list in mctp_lookup_prealloc_tag()\n\nWhen a socket transmits a packet with MCTP_TAG_PREALLOC set,\nmctp_lookup_prealloc_tag() iterates over the per-netns &mns->keys list\nand matches netid, req_tag, peer_addr, and manual_alloc, without\nchecking whether tmp->sk == &msk->sk. This allows any MCTP socket in the\nsame network namespace to use and consume another socket's preallocated\ntag.\n\nIterate the socket's own tag list (&msk->keys via sklist) instead of the\nnamespace-wide &mns->keys list in mctp_lookup_prealloc_tag(), ensuring\nthat only tags allocated by msk are matched.\n\nTested in QEMU against Linux 7.3.0-rc3 by allocating a manual tag\n(0x18) on socket A via SIOCMCTPALLOCTAG for peer EID 9 and sending a\n4-byte message with MCTP_TAG_PREALLOC from socket B in the same network\nnamespace. On the unfixed kernel, sendto(sock_b) using socket A's\npreallocated tag succeeds (ret = 4); with this patch applied,\nsendto(sock_b) fails with -ENOENT (errno = 2) while sendto(sock_a)\nsucceeds (ret = 4)."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/mctp/route.c"], "versions": [{"version": "63ed1aab3d40aa61aaa66819bdce9377ac7f40fa", "lessThan": "09299addab11857e92eca55cd8ef3350b927c90c", "status": "affected", "versionType": "git"}, {"version": "63ed1aab3d40aa61aaa66819bdce9377ac7f40fa", "lessThan": "e35cb500dd14882f8dee61783fccd1823fd3ab0d", "status": "affected", "versionType": "git"}, {"version": "63ed1aab3d40aa61aaa66819bdce9377ac7f40fa", "lessThan": "f178300e2f56ca9ec2a3a0090608730bbee0af7b", "status": "affected", "versionType": "git"}, {"version": "63ed1aab3d40aa61aaa66819bdce9377ac7f40fa", "lessThan": "26cc0e69cce062cd3aa6fae33074684669c35a71", "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/mctp/route.c"], "versions": [{"version": "5.18", "status": "affected"}, {"version": "0", "lessThan": "5.18", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.112", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.55", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.9", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "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": "5.18", "versionEndExcluding": "6.12.112"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.18", "versionEndExcluding": "6.18.55"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.18", "versionEndExcluding": "7.2.9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.18", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/09299addab11857e92eca55cd8ef3350b927c90c"}, {"url": "https://git.kernel.org/stable/c/e35cb500dd14882f8dee61783fccd1823fd3ab0d"}, {"url": "https://git.kernel.org/stable/c/f178300e2f56ca9ec2a3a0090608730bbee0af7b"}, {"url": "https://git.kernel.org/stable/c/26cc0e69cce062cd3aa6fae33074684669c35a71"}], "title": "mctp: route: iterate socket tag list in mctp_lookup_prealloc_tag()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/mctp/route.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "09299addab11857e92eca55cd8ef3350b927c90c", "status": "affected", "version": "63ed1aab3d40aa61aaa66819bdce9377ac7f40fa", "versionType": "git"}, {"lessThan": "e35cb500dd14882f8dee61783fccd1823fd3ab0d", "status": "affected", "version": "63ed1aab3d40aa61aaa66819bdce9377ac7f40fa", "versionType": "git"}, {"lessThan": "f178300e2f56ca9ec2a3a0090608730bbee0af7b", "status": "affected", "version": "63ed1aab3d40aa61aaa66819bdce9377ac7f40fa", "versionType": "git"}, {"lessThan": "26cc0e69cce062cd3aa6fae33074684669c35a71", "status": "affected", "version": "63ed1aab3d40aa61aaa66819bdce9377ac7f40fa", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/mctp/route.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.18"}, {"lessThan": "5.18", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.112", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.55", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.9", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "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\nmctp: route: iterate socket tag list in mctp_lookup_prealloc_tag()\n\nWhen a socket transmits a packet with MCTP_TAG_PREALLOC set,\nmctp_lookup_prealloc_tag() iterates over the per-netns &mns->keys list\nand matches netid, req_tag, peer_addr, and manual_alloc, without\nchecking whether tmp->sk == &msk->sk. This allows any MCTP socket in the\nsame network namespace to use and consume another socket's preallocated\ntag.\n\nIterate the socket's own tag list (&msk->keys via sklist) instead of the\nnamespace-wide &mns->keys list in mctp_lookup_prealloc_tag(), ensuring\nthat only tags allocated by msk are matched.\n\nTested in QEMU against Linux 7.3.0-rc3 by allocating a manual tag\n(0x18) on socket A via SIOCMCTPALLOCTAG for peer EID 9 and sending a\n4-byte message with MCTP_TAG_PREALLOC from socket B in the same network\nnamespace. On the unfixed kernel, sendto(sock_b) using socket A's\npreallocated tag succeeds (ret = 4); with this patch applied,\nsendto(sock_b) fails with -ENOENT (errno = 2) while sendto(sock_a)\nsucceeds (ret = 4)."}], "id": "CVE-2026-98525", "lastModified": "2026-10-19T10:19:07.707", "metrics": {}, "published": "2026-10-18T16:17:03.953", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/09299addab11857e92eca55cd8ef3350b927c90c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/26cc0e69cce062cd3aa6fae33074684669c35a71"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e35cb500dd14882f8dee61783fccd1823fd3ab0d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f178300e2f56ca9ec2a3a0090608730bbee0af7b"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: mctp: route: iterate socket tag list in mctp_lookup_prealloc_tag()", "id": "2555012", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2555012"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.4", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L", "status": "draft"}, "cwe": "CWE-283", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nmctp: route: iterate socket tag list in mctp_lookup_prealloc_tag()\nWhen a socket transmits a packet with MCTP_TAG_PREALLOC set,\nmctp_lookup_prealloc_tag() iterates over the per-netns &mns->keys list\nand matches netid, req_tag, peer_addr, and manual_alloc, without\nchecking whether tmp->sk == &msk->sk. This allows any MCTP socket in the\nsame network namespace to use and consume another socket's preallocated\ntag.\nIterate the socket's own tag list (&msk->keys via sklist) instead of the\nnamespace-wide &mns->keys list in mctp_lookup_prealloc_tag(), ensuring\nthat only tags allocated by msk are matched.\nTested in QEMU against Linux 7.3.0-rc3 by allocating a manual tag\n(0x18) on socket A via SIOCMCTPALLOCTAG for peer EID 9 and sending a\n4-byte message with MCTP_TAG_PREALLOC from socket B in the same network\nnamespace. On the unfixed kernel, sendto(sock_b) using socket A's\npreallocated tag succeeds (ret = 4); with this patch applied,\nsendto(sock_b) fails with -ENOENT (errno = 2) while sendto(sock_a)\nsucceeds (ret = 4).", "A flaw was found in the Linux kernel's Management Component Transport Protocol (MCTP) subsystem. When looking up preallocated communication tags, the kernel fails to verify that a requested tag belongs to the calling socket and instead searches across the entire network namespace. A local attacker can exploit this flaw to consume another socket's preallocated tags, leading to communication disruption or unauthorized message transmission."], "name": "CVE-2026-98525", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "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": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-10-18T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-98525\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-98525\nhttps://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98525.mbox"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[63ed1aab3d40aa61aaa66819bdce9377ac7f40fa,09299addab11857e92eca55cd8ef3350b927c90c)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[63ed1aab3d40aa61aaa66819bdce9377ac7f40fa,e35cb500dd14882f8dee61783fccd1823fd3ab0d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[63ed1aab3d40aa61aaa66819bdce9377ac7f40fa,f178300e2f56ca9ec2a3a0090608730bbee0af7b)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[63ed1aab3d40aa61aaa66819bdce9377ac7f40fa,26cc0e69cce062cd3aa6fae33074684669c35a71)"}}], "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": "5.18"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,5.18)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.112,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.55,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.9,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3,*]"}}], "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": "2026-10-18T23:30:14.147771+00:00", "updated": "2026-10-20T16:30:06.799229+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}