{ "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": "2026-10-19T08:52:35.697Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:52:35.697Z" }, "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", "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" } ] } ] } ], "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" } } } }