{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-68399", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.389Z", "datePublished": "2026-08-10T12:04:18.837Z", "dateUpdated": "2026-10-16T15:53:11.889Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-15T10:08:24.934Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix UAF in sock clone early bailouts\n\nSimilar to recent commit 9b51a6155d14 (\"bpf,fork: wipe ->bpf_storage\nbefore bailouts that access it\"), sk_clone() performs an initial\nshallow copy of the socket field ->sk_bpf_storage via sock_copy()\nfor the cloned socket newsk.\n\nIf sk_clone() bails out early (e.g. if sk_filter_charge() fails) prior\nto calling bpf_sk_storage_clone(), newsk->sk_bpf_storage still points\nto the parent socket's BPF local storage. When newsk is subsequently\nfreed via sk_free(), the deallocation path (__sk_destruct() ->\nbpf_sk_storage_free()) destroys the parent socket's BPF local storage,\nleading to a use-after-free (UAF) on the parent socket.\n\nFix this by resetting newsk->sk_bpf_storage to NULL immediately after\nsock_copy() in sk_clone(), and remove the now redundant initialization\nfrom bpf_sk_storage_clone()." } ], "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 vulnerable clone path and its early-bailout condition are driven through the BPF sk_storage subsystem and local socket setup (attaching sk_storage, attaching a socket filter, adjusting optmem_max). Per kernel guidance BPF is Local; a remote peer cannot control the bailout conditions.\nAC:L - An attacker who controls the local setup can deterministically force the early bailout by attaching a filter and lowering net.core.optmem_max below the filter size, exactly the sysctl-change scenario the code documents, making sk_filter_charge fail on every clone.\nPR:L - Reaching the bug requires attaching BPF sk_storage and manipulating socket/net settings; these capabilities (CAP_BPF/CAP_NET_ADMIN) can be reachable via user namespaces in some configurations, so the lower-privilege value is chosen per the higher-severity rule.\nUI:N - The clone is triggered by connection acceptance or association creation with no victim action; no user interaction is needed.\nS:U - The UAF corrupts kernel socket/BPF-storage objects within the kernel's own security authority; no crossing into a separate security scope (no VM/IOMMU boundary).\nC:H - The use-after-free lets the attacker reclaim the freed bpf_local_storage object with controlled contents, enabling disclosure of kernel memory; per guidance UAF is High.\nI:H - UAF on a live socket's BPF storage enables heap grooming and arbitrary-write primitives, giving control-flow hijack potential; per guidance UAF is High.\nA:H - Destroying the parent socket's still-referenced BPF local storage reliably causes memory corruption, oops, and kernel panic; per guidance any UAF/crash is High." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/bpf_sk_storage.c", "net/core/sock.c" ], "versions": [ { "version": "6ac99e8f23d4b10258406ca0dd7bffca5f31da9d", "lessThan": "01f8a354497ba739f81b691b3702bc4c46500a4d", "status": "affected", "versionType": "git" }, { "version": "6ac99e8f23d4b10258406ca0dd7bffca5f31da9d", "lessThan": "14b49b5ab29979552c219a09e569b424fbbf4a6e", "status": "affected", "versionType": "git" }, { "version": "6ac99e8f23d4b10258406ca0dd7bffca5f31da9d", "lessThan": "7cbd0c4cebe4c9f678d15e6b9ba975e1155a107f", "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/core/bpf_sk_storage.c", "net/core/sock.c" ], "versions": [ { "version": "5.2", "status": "affected" }, { "version": "0", "lessThan": "5.2", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.57", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.6", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "5.2", "versionEndExcluding": "6.18.57" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.2", "versionEndExcluding": "7.1.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.2", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/01f8a354497ba739f81b691b3702bc4c46500a4d" }, { "url": "https://git.kernel.org/stable/c/14b49b5ab29979552c219a09e569b424fbbf4a6e" }, { "url": "https://git.kernel.org/stable/c/7cbd0c4cebe4c9f678d15e6b9ba975e1155a107f" } ], "title": "bpf: Fix UAF in sock clone early bailouts", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-68399", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T15:48:12.954788Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T15:53:11.889Z" } } ] } }