{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-46099", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-13T15:03:33.097Z", "datePublished": "2026-05-27T12:59:04.628Z", "dateUpdated": "2026-06-01T16:18:15.820Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-06-01T16:18:15.820Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ipv6: fix NOREF dst use in seg6 and rpl lwtunnels\n\nseg6_input_core() and rpl_input() call ip6_route_input() which sets a\nNOREF dst on the skb, then pass it to dst_cache_set_ip6() invoking\ndst_hold() unconditionally.\nOn PREEMPT_RT, ksoftirqd is preemptible and a higher-priority task can\nrelease the underlying pcpu_rt between the lookup and the caching\nthrough a concurrent FIB lookup on a shared nexthop.\nSimplified race sequence:\n\n ksoftirqd/X higher-prio task (same CPU X)\n ----------- --------------------------------\n seg6_input_core(,skb)/rpl_input(skb)\n dst_cache_get()\n -> miss\n ip6_route_input(skb)\n -> ip6_pol_route(,skb,flags)\n [RT6_LOOKUP_F_DST_NOREF in flags]\n -> FIB lookup resolves fib6_nh\n [nhid=N route]\n -> rt6_make_pcpu_route()\n [creates pcpu_rt, refcount=1]\n pcpu_rt->sernum = fib6_sernum\n [fib6_sernum=W]\n -> cmpxchg(fib6_nh.rt6i_pcpu,\n NULL, pcpu_rt)\n [slot was empty, store succeeds]\n -> skb_dst_set_noref(skb, dst)\n [dst is pcpu_rt, refcount still 1]\n\n rt_genid_bump_ipv6()\n -> bumps fib6_sernum\n [fib6_sernum from W to Z]\n ip6_route_output()\n -> ip6_pol_route()\n -> FIB lookup resolves fib6_nh\n [nhid=N]\n -> rt6_get_pcpu_route()\n pcpu_rt->sernum != fib6_sernum\n [W <> Z, stale]\n -> prev = xchg(rt6i_pcpu, NULL)\n -> dst_release(prev)\n [prev is pcpu_rt,\n refcount 1->0, dead]\n\n dst = skb_dst(skb)\n [dst is the dead pcpu_rt]\n dst_cache_set_ip6(dst)\n -> dst_hold() on dead dst\n -> WARN / use-after-free\n\nFor the race to occur, ksoftirqd must be preemptible (PREEMPT_RT without\nPREEMPT_RT_NEEDS_BH_LOCK) and a concurrent task must be able to release\nthe pcpu_rt. Shared nexthop objects provide such a path, as two routes\npointing to the same nhid share the same fib6_nh and its rt6i_pcpu\nentry.\n\nFix seg6_input_core() and rpl_input() by calling skb_dst_force() after\nip6_route_input() to force the NOREF dst into a refcounted one before\ncaching.\nThe output path is not affected as ip6_route_output() already returns a\nrefcounted dst."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.1, "baseSeverity": "HIGH"}}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/ipv6/rpl_iptunnel.c", "net/ipv6/seg6_iptunnel.c"], "versions": [{"version": "af4a2209b1344939eaac11f269c261d347cbc3ee", "lessThan": "51fef5a7c4d160839199e941929456ba21ddf73c", "status": "affected", "versionType": "git"}, {"version": "af4a2209b1344939eaac11f269c261d347cbc3ee", "lessThan": "b258b849a580285a1692e782ebc902b44c884a71", "status": "affected", "versionType": "git"}, {"version": "af4a2209b1344939eaac11f269c261d347cbc3ee", "lessThan": "6bd17925bd6866027a6555db17905b9fc073d38d", "status": "affected", "versionType": "git"}, {"version": "af4a2209b1344939eaac11f269c261d347cbc3ee", "lessThan": "52f9db67f8f35f436366cf4980b4f0a2583d0ef0", "status": "affected", "versionType": "git"}, {"version": "af4a2209b1344939eaac11f269c261d347cbc3ee", "lessThan": "b778b6d095421619c331fd2d7751143cd5387103", "status": "affected", "versionType": "git"}, {"version": "af4a2209b1344939eaac11f269c261d347cbc3ee", "lessThan": "9dd5481f960e337b81d7dfe429529495c1c481c0", "status": "affected", "versionType": "git"}, {"version": "af4a2209b1344939eaac11f269c261d347cbc3ee", "lessThan": "f9c52a6ba9780bd27e0bf4c044fd91c13c778b6e", "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/rpl_iptunnel.c", "net/ipv6/seg6_iptunnel.c"], "versions": [{"version": "4.12", "status": "affected"}, {"version": "0", "lessThan": "4.12", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.209", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.175", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.140", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.86", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.27", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0.4", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1-rc2", "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": "4.12", "versionEndExcluding": "5.15.209"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.1.175"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.6.140"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.12.86"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.18.27"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "7.0.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "7.1-rc2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/51fef5a7c4d160839199e941929456ba21ddf73c"}, {"url": "https://git.kernel.org/stable/c/b258b849a580285a1692e782ebc902b44c884a71"}, {"url": "https://git.kernel.org/stable/c/6bd17925bd6866027a6555db17905b9fc073d38d"}, {"url": "https://git.kernel.org/stable/c/52f9db67f8f35f436366cf4980b4f0a2583d0ef0"}, {"url": "https://git.kernel.org/stable/c/b778b6d095421619c331fd2d7751143cd5387103"}, {"url": "https://git.kernel.org/stable/c/9dd5481f960e337b81d7dfe429529495c1c481c0"}, {"url": "https://git.kernel.org/stable/c/f9c52a6ba9780bd27e0bf4c044fd91c13c778b6e"}], "title": "net: ipv6: fix NOREF dst use in seg6 and rpl lwtunnels", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ipv6: fix NOREF dst use in seg6 and rpl lwtunnels\n\nseg6_input_core() and rpl_input() call ip6_route_input() which sets a\nNOREF dst on the skb, then pass it to dst_cache_set_ip6() invoking\ndst_hold() unconditionally.\nOn PREEMPT_RT, ksoftirqd is preemptible and a higher-priority task can\nrelease the underlying pcpu_rt between the lookup and the caching\nthrough a concurrent FIB lookup on a shared nexthop.\nSimplified race sequence:\n\n ksoftirqd/X higher-prio task (same CPU X)\n ----------- --------------------------------\n seg6_input_core(,skb)/rpl_input(skb)\n dst_cache_get()\n -> miss\n ip6_route_input(skb)\n -> ip6_pol_route(,skb,flags)\n [RT6_LOOKUP_F_DST_NOREF in flags]\n -> FIB lookup resolves fib6_nh\n [nhid=N route]\n -> rt6_make_pcpu_route()\n [creates pcpu_rt, refcount=1]\n pcpu_rt->sernum = fib6_sernum\n [fib6_sernum=W]\n -> cmpxchg(fib6_nh.rt6i_pcpu,\n NULL, pcpu_rt)\n [slot was empty, store succeeds]\n -> skb_dst_set_noref(skb, dst)\n [dst is pcpu_rt, refcount still 1]\n\n rt_genid_bump_ipv6()\n -> bumps fib6_sernum\n [fib6_sernum from W to Z]\n ip6_route_output()\n -> ip6_pol_route()\n -> FIB lookup resolves fib6_nh\n [nhid=N]\n -> rt6_get_pcpu_route()\n pcpu_rt->sernum != fib6_sernum\n [W <> Z, stale]\n -> prev = xchg(rt6i_pcpu, NULL)\n -> dst_release(prev)\n [prev is pcpu_rt,\n refcount 1->0, dead]\n\n dst = skb_dst(skb)\n [dst is the dead pcpu_rt]\n dst_cache_set_ip6(dst)\n -> dst_hold() on dead dst\n -> WARN / use-after-free\n\nFor the race to occur, ksoftirqd must be preemptible (PREEMPT_RT without\nPREEMPT_RT_NEEDS_BH_LOCK) and a concurrent task must be able to release\nthe pcpu_rt. Shared nexthop objects provide such a path, as two routes\npointing to the same nhid share the same fib6_nh and its rt6i_pcpu\nentry.\n\nFix seg6_input_core() and rpl_input() by calling skb_dst_force() after\nip6_route_input() to force the NOREF dst into a refcounted one before\ncaching.\nThe output path is not affected as ip6_route_output() already returns a\nrefcounted dst."}], "id": "CVE-2026-46099", "lastModified": "2026-06-01T17:17:23.787", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 8.1, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 2.2, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-05-27T14:17:31.557", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/51fef5a7c4d160839199e941929456ba21ddf73c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/52f9db67f8f35f436366cf4980b4f0a2583d0ef0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/6bd17925bd6866027a6555db17905b9fc073d38d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/9dd5481f960e337b81d7dfe429529495c1c481c0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b258b849a580285a1692e782ebc902b44c884a71"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b778b6d095421619c331fd2d7751143cd5387103"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f9c52a6ba9780bd27e0bf4c044fd91c13c778b6e"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Awaiting Analysis"}

{"bugzilla": {"description": "kernel: net: ipv6: fix NOREF dst use in seg6 and rpl lwtunnels", "id": "2481972", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2481972"}, "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-911", "details": ["A flaw was found in the Linux kernel's IPv6 networking implementation, specifically within the `seg6` and `rpl` lwtunnels. A race condition can occur when handling destination cache entries, where a `NOREF` (no reference) destination object is used after it has been freed. This use-after-free vulnerability can lead to system instability or a denial of service (DoS) on systems configured with `PREEMPT_RT` (Preemptible Real-Time) kernel."], "name": "CVE-2026-46099", "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": "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": "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": "2026-05-27T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-46099\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-46099\nhttps://lore.kernel.org/linux-cve-announce/2026052704-CVE-2026-46099-2a55@gregkh/T"], "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af4a2209b1344939eaac11f269c261d347cbc3ee,6bd17925bd6866027a6555db17905b9fc073d38d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af4a2209b1344939eaac11f269c261d347cbc3ee,52f9db67f8f35f436366cf4980b4f0a2583d0ef0)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af4a2209b1344939eaac11f269c261d347cbc3ee,b778b6d095421619c331fd2d7751143cd5387103)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af4a2209b1344939eaac11f269c261d347cbc3ee,9dd5481f960e337b81d7dfe429529495c1c481c0)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af4a2209b1344939eaac11f269c261d347cbc3ee,f9c52a6ba9780bd27e0bf4c044fd91c13c778b6e)"}}], "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": "4.12"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,4.12)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.140,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.86,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.27,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.0.4,7.1.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1-rc2,*]"}}], "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": "2026-05-27T18:00:15.755263+00:00", "updated": "2026-05-30T13:30:24.557364+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}