{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89783","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.765Z","datePublished":"2026-09-16T08:48:21.761Z","dateUpdated":"2026-09-16T14:38:34.989Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-16T14:38:34.989Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm6: fix out-of-bounds write in xfrm6_input_addr() when secpath is full\n\nThe depth check in xfrm6_input_addr() is off by one:\n\n  if (1 + sp->len == XFRM_MAX_DEPTH)\n          goto drop;\n  ...\n  sp->xvec[sp->len++] = x;\n\nxfrm_input() can leave sp->len == XFRM_MAX_DEPTH, and the transport-mode\nreceive path re-enters IPv6 input via xfrm_trans_reinject() with that\nsecpath preserved. If the inner packet carries a destination-options HAO\noption or a type-2 routing header, xfrm6_input_addr() is called with\nsp->len == XFRM_MAX_DEPTH; the check (1 + 6 == 6) is false, so\nsp->xvec[sp->len++] writes one slot past the 6-element xvec[]. The write\nstays within the sec_path allocation (invisible to KASAN); UBSAN_BOUNDS\nflags it and panics under panic_on_warn.\n\nUse \"sp->len >= XFRM_MAX_DEPTH\", matching xfrm_input(). This also\nrestores one chain level the old check rejected at sp->len == 5.\n\n  UBSAN: array-index-out-of-bounds in net/ipv6/xfrm6_input.c:309:10\n  index 6 is out of range for type 'xfrm_state *[6]'"}],"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 on the IPv6 receive path: remote ESP/AH packets are processed by xfrm_input() until the secpath is full, then xfrm_trans_reinject() re-enters ip6_rcv_finish so an inner destopt HAO or type-2 routing header reaches xfrm6_input_addr() on internet-facing IPsec/MIP6 VPN and home-agent endpoints.\nAC:L - Once a max-depth transport-mode IPsec bundle and a MIP6 destopt or routing state are present, a peer sending nested IPsec then an inner HAO or type-2 RH deterministically bypasses the off-by-one check (1+6!=6) and writes xvec[6]; no race or attacker-uncontrollable layout is required.\nPR:N - No local account or capability on the victim is required. A remote IPsec/MIP6 peer triggers the overflow with packets accepted by already-installed SAs; creating those SAs is a deployment precondition rather than attacker privilege on the host.\nUI:N - Packets are processed in NAPI/softirq and the deferred xfrm_trans_reinject workqueue with no victim action such as mounting a filesystem, opening a file, or otherwise interacting with the host.\nS:U - The out-of-bounds write corrupts the skb sec_path in the host kernel that processed the packet; this is standard kernel memory corruption, not a VM escape, IOMMU bypass, or other cross-authority boundary.\nC:H - The overflow writes a kernel xfrm_state pointer past xvec[] into the adjacent xfrm_offload object and sets len to 7, so later xvec walks and teardown treat that overlapping memory as a state pointer, giving a memory-corruption disclosure primitive.\nI:H - This is an out-of-bounds write of a kernel pointer one slot past the 6-element xvec[] into ovec, which per kernel CVSS guidance is high integrity impact and can be shaped toward control-flow hijacking.\nA:H - UBSAN_BOUNDS flags the overflow and panics under panic_on_warn, and the corrupted sec_path (len=7 overlapping ovec) can oops during later xvec iteration or skb_ext teardown, fully denying availability."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/xfrm6_input.c"],"versions":[{"version":"9473e1f631de339c50bde1e3bd09e1045fe90fd5","lessThan":"91fc387f63c00ddfb5221127a17bac97549a8343","status":"affected","versionType":"git"},{"version":"9473e1f631de339c50bde1e3bd09e1045fe90fd5","lessThan":"68e8737fe8e72f085c608cff322b3d2de8340af1","status":"affected","versionType":"git"},{"version":"9473e1f631de339c50bde1e3bd09e1045fe90fd5","lessThan":"8fe2c53fb81f5ad5be43af2ad09583f7c78b4b77","status":"affected","versionType":"git"},{"version":"9473e1f631de339c50bde1e3bd09e1045fe90fd5","lessThan":"bdcda866c89f9a8b1acdabf02d26cde9fbe501d8","status":"affected","versionType":"git"},{"version":"9473e1f631de339c50bde1e3bd09e1045fe90fd5","lessThan":"48996649222e95008cdb98cd58579e3fc8e5ee06","status":"affected","versionType":"git"},{"version":"9473e1f631de339c50bde1e3bd09e1045fe90fd5","lessThan":"0f679e0523ddfff3fb554336ceb874b0e51e9cd3","status":"affected","versionType":"git"},{"version":"9473e1f631de339c50bde1e3bd09e1045fe90fd5","lessThan":"5f35a29a5eed3d80befd32050843ac88dea3d61a","status":"affected","versionType":"git"},{"version":"9473e1f631de339c50bde1e3bd09e1045fe90fd5","lessThan":"5d9e3bf34fec9a5d237e4b7cef4a707bc2e091bc","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/xfrm6_input.c"],"versions":[{"version":"2.6.25","status":"affected"},{"version":"0","lessThan":"2.6.25","status":"unaffected","versionType":"semver"},{"version":"5.10.270","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.221","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.188","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.157","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.110","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.52","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.6","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","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":"2.6.25","versionEndExcluding":"5.10.270"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.18.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"7.3-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/91fc387f63c00ddfb5221127a17bac97549a8343"},{"url":"https://git.kernel.org/stable/c/68e8737fe8e72f085c608cff322b3d2de8340af1"},{"url":"https://git.kernel.org/stable/c/8fe2c53fb81f5ad5be43af2ad09583f7c78b4b77"},{"url":"https://git.kernel.org/stable/c/bdcda866c89f9a8b1acdabf02d26cde9fbe501d8"},{"url":"https://git.kernel.org/stable/c/48996649222e95008cdb98cd58579e3fc8e5ee06"},{"url":"https://git.kernel.org/stable/c/0f679e0523ddfff3fb554336ceb874b0e51e9cd3"},{"url":"https://git.kernel.org/stable/c/5f35a29a5eed3d80befd32050843ac88dea3d61a"},{"url":"https://git.kernel.org/stable/c/5d9e3bf34fec9a5d237e4b7cef4a707bc2e091bc"}],"title":"xfrm6: fix out-of-bounds write in xfrm6_input_addr() when secpath is full","x_generator":{"engine":"bippy-1.2.0"}}}}