CVE-2026-90111

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-90111", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.787Z", "datePublished": "2026-09-17T16:06:18.779Z", "dateUpdated": "2026-10-30T12:34:13.088Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:34:13.088Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nip6mr: do not clone dst in ip6mr_cache_report()\n\nIPv6 input attaches a non-refcounted (NOREF) dst to skbs under RCU.\nWhen an ingress multicast packet misses MFC lookup,\nip6mr_cache_unresolved() places the skb onto the unresolved queue,\nescaping the receive-side RCU grace period.\n\nIf the underlying route is deleted and freed, and the MFC queue is later\nresolved with a wrong parent interface, ip6_mr_forward() invokes\nip6mr_cache_report(..., MRT6MSG_WRONGMIF), which executes\ndst_clone(skb_dst(pkt)) on the freed dst entry, triggering a slab\nuse-after-free.\n\nReport packets queued to mroute6_sk (a raw socket) and netlink\nnotifications do not require an attached dst entry.\n\nFix this by:\n1. Removing dst_clone() in ip6mr_cache_report() and ensuring report skbs\n do not hold a dst.\n2. Dropping skb_dst before queuing unresolved skbs in\n ip6mr_cache_unresolved(), matching the fact that multicast\n forwarding resolves outgoing routes anew via ip6_route_output()."}], "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 UAF is dst_clone(skb_dst(pkt)) in ip6mr_cache_report(MRT6MSG_WRONGMIF) on a NOREF dst that ip6_route_input() attached and ip6mr_cache_unresolved() queued past RCU. Completing it requires deleting that fib6 route and MRT6_ADD_MFC with mf6cc_parent != the arrival vif; those are local setsockopt/netlink from the same attacker, not a field in the IPv6 multicast datagram.\nAC:L - The attacker owns every step: MRT6_INIT/ADD_MIF/ASSERT, inject a non-link-local IPv6 multicast skb so ip6_mr_input() misses the MFC and ip6mr_cache_unresolved() queues it, delete the fib6 route and wait an RCU grace period, then MRT6_ADD_MFC with the wrong parent so ip6_mr_forward() takes the WRONGMIF path.\nPR:L - inet6_create() allows SOCK_RAW/IPPROTO_ICMPV6 only with ns_capable(CAP_NET_RAW); ip6_mroute_setsockopt() then lets that mroute socket (or ns_capable(CAP_NET_ADMIN)) run MRT6_ADD_MIF, MRT6_ASSERT, and MRT6_ADD_MFC. An unprivileged user obtains both capabilities in a user+net namespace via unshare -Urn.\nUI:N - The attacker opens the raw ICMPv6 mroute socket, adds MIFs, injects the multicast skb onto a veth, deletes the fib6 route, and installs the mismatched-parent MFC entirely with their own syscalls; no other user must mount a volume or otherwise interact.\nS:U - dst_clone()/dst_hold() touch the host kernel's struct dst_entry from the IPv6 fib looked up for the queued skb; the use-after-free stays in that networking authority and does not cross a VM, IOMMU, or other boundary.\nC:H - After the fib6 route is freed, ip6mr_cache_report() still does dst_clone(skb_dst(pkt)) and dst_hold() reads __rcuref on the dangling dst_entry; that slab UAF can be reclaimed with attacker-controlled objects and used as an arbitrary kernel read.\nI:H - dst_hold() calls rcuref_get(&dst->__rcuref) on the freed dst_entry, writing a reclaimable slab object that can be sprayed to forge a refcount/control-flow hijack when the WRONGMIF report clones the stale dst.\nA:H - ip6_mr_forward() invoking ip6mr_cache_report(MRT6MSG_WRONGMIF) oopses in dst_hold()/rcuref_get() on the already-freed dst_entry even without a full exploit, so the bug is a reliable kernel crash as well as a UAF."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/ipv6/ip6mr.c"], "versions": [{"version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "lessThan": "b50d3cfb8513e895cee453dd0f834deee6ccc231", "status": "affected", "versionType": "git"}, {"version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "lessThan": "7f8287f606c8c028d4224e85d95dc448c6d6d623", "status": "affected", "versionType": "git"}, {"version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "lessThan": "42ef371466d5648f5c9e8bc219f0af0a2c2bbf8c", "status": "affected", "versionType": "git"}, {"version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "lessThan": "f57b0fd1c62e1be274ee154ab7fb8ac4481b7f89", "status": "affected", "versionType": "git"}, {"version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "lessThan": "4a674afaae4136c71943aa3e35d433676fd40e8f", "status": "affected", "versionType": "git"}, {"version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "lessThan": "235b42b5860189eb8c27c36435ad932cae65a734", "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/ipv6/ip6mr.c"], "versions": [{"version": "5.3", "status": "affected"}, {"version": "0", "lessThan": "5.3", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.191", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.114", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.57", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.6", "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": "5.3", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.12.114"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.18.57"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "7.2.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/b50d3cfb8513e895cee453dd0f834deee6ccc231"}, {"url": "https://git.kernel.org/stable/c/7f8287f606c8c028d4224e85d95dc448c6d6d623"}, {"url": "https://git.kernel.org/stable/c/42ef371466d5648f5c9e8bc219f0af0a2c2bbf8c"}, {"url": "https://git.kernel.org/stable/c/f57b0fd1c62e1be274ee154ab7fb8ac4481b7f89"}, {"url": "https://git.kernel.org/stable/c/4a674afaae4136c71943aa3e35d433676fd40e8f"}, {"url": "https://git.kernel.org/stable/c/235b42b5860189eb8c27c36435ad932cae65a734"}], "title": "ip6mr: do not clone dst in ip6mr_cache_report()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/ipv6/ip6mr.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "b50d3cfb8513e895cee453dd0f834deee6ccc231", "status": "affected", "version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "versionType": "git"}, {"lessThan": "7f8287f606c8c028d4224e85d95dc448c6d6d623", "status": "affected", "version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "versionType": "git"}, {"lessThan": "42ef371466d5648f5c9e8bc219f0af0a2c2bbf8c", "status": "affected", "version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "versionType": "git"}, {"lessThan": "f57b0fd1c62e1be274ee154ab7fb8ac4481b7f89", "status": "affected", "version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "versionType": "git"}, {"lessThan": "4a674afaae4136c71943aa3e35d433676fd40e8f", "status": "affected", "version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "versionType": "git"}, {"lessThan": "235b42b5860189eb8c27c36435ad932cae65a734", "status": "affected", "version": "67f415dd29063a5906c560051c00e42dcf01a4dd", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/ipv6/ip6mr.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.3"}, {"lessThan": "5.3", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.160", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.114", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.57", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.6", "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\nip6mr: do not clone dst in ip6mr_cache_report()\n\nIPv6 input attaches a non-refcounted (NOREF) dst to skbs under RCU.\nWhen an ingress multicast packet misses MFC lookup,\nip6mr_cache_unresolved() places the skb onto the unresolved queue,\nescaping the receive-side RCU grace period.\n\nIf the underlying route is deleted and freed, and the MFC queue is later\nresolved with a wrong parent interface, ip6_mr_forward() invokes\nip6mr_cache_report(..., MRT6MSG_WRONGMIF), which executes\ndst_clone(skb_dst(pkt)) on the freed dst entry, triggering a slab\nuse-after-free.\n\nReport packets queued to mroute6_sk (a raw socket) and netlink\nnotifications do not require an attached dst entry.\n\nFix this by:\n1. Removing dst_clone() in ip6mr_cache_report() and ensuring report skbs\n do not hold a dst.\n2. Dropping skb_dst before queuing unresolved skbs in\n ip6mr_cache_unresolved(), matching the fact that multicast\n forwarding resolves outgoing routes anew via ip6_route_output()."}], "id": "CVE-2026-90111", "lastModified": "2026-10-30T13:20:42.083", "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"}]}, "published": "2026-09-17T17:17:03.130", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/235b42b5860189eb8c27c36435ad932cae65a734"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/42ef371466d5648f5c9e8bc219f0af0a2c2bbf8c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4a674afaae4136c71943aa3e35d433676fd40e8f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7f8287f606c8c028d4224e85d95dc448c6d6d623"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b50d3cfb8513e895cee453dd0f834deee6ccc231"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f57b0fd1c62e1be274ee154ab7fb8ac4481b7f89"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[67f415dd29063a5906c560051c00e42dcf01a4dd,4a674afaae4136c71943aa3e35d433676fd40e8f)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[67f415dd29063a5906c560051c00e42dcf01a4dd,235b42b5860189eb8c27c36435ad932cae65a734)"}}], "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": "5.3"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,5.3)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.6,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-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": "2026-09-18T18:00:11.769173+00:00", "updated": "2026-09-20T03:00:11.261475+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-416"]}