{"id":"CVE-2026-63987","state":"PUBLISHED","title":"ethtool: coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nethtool: coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES\n\nethnl_update_profile() walks the ETHTOOL_A_PROFILE_IRQ_MODERATION\nnest list with an index 'i' and writes new_profile[i++] without\nbounding i. The destination is kmemdup()'d at NET_DIM_PARAMS_NUM_PROFILES\nentries (5), but the Netlink nest count is entirely user-controlled.\nNetlink policies do not have support for constraining the number\nof nested entries (or number of multi-attr entries).","publishedAt":"2026-07-19T14:56:08.940Z","updatedAt":"2026-10-19T20:18:01.044Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f750dfe825b904164688adeb147950e0e0c4d262","status":"affected","lessThan":"d4c9cc7c47781c6f4fa29d80a1193a8bcd1525bc","versionType":"git"},{"version":"f750dfe825b904164688adeb147950e0e0c4d262","status":"affected","lessThan":"0c02c190bcd9822477038ff2cee10ea584ac1b1d","versionType":"git"},{"version":"f750dfe825b904164688adeb147950e0e0c4d262","status":"affected","lessThan":"6205f7166d2dd14a017a5802c81e5bd1421a8635","versionType":"git"},{"version":"f750dfe825b904164688adeb147950e0e0c4d262","status":"affected","lessThan":"7281b096b072f6c6e30420e3467d738f2e4c4b57","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ethtool/coalesce.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.11","versionType":"semver"},{"version":"6.12.93","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.35","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.12","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ethtool/coalesce.c"]}],"references":["https://git.kernel.org/stable/c/d4c9cc7c47781c6f4fa29d80a1193a8bcd1525bc","https://git.kernel.org/stable/c/0c02c190bcd9822477038ff2cee10ea584ac1b1d","https://git.kernel.org/stable/c/6205f7166d2dd14a017a5802c81e5bd1421a8635","https://git.kernel.org/stable/c/7281b096b072f6c6e30420e3467d738f2e4c4b57"],"weaknesses":["CWE-787"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/63xxx/CVE-2026-63987.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-63987","state":"PUBLISHED","datePublished":"2026-07-19T14:56:08.940Z","dateUpdated":"2026-10-19T20:18:01.044Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T07:54:57.025Z"},"containers":{"cna":{"title":"ethtool: coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nethtool: coalesce: cap profile updates at NET_DIM_PARAMS_NUM_PROFILES\n\nethnl_update_profile() walks the ETHTOOL_A_PROFILE_IRQ_MODERATION\nnest list with an index 'i' and writes new_profile[i++] without\nbounding i. The destination is kmemdup()'d at NET_DIM_PARAMS_NUM_PROFILES\nentries (5), but the Netlink nest count is entirely user-controlled.\nNetlink policies do not have support for constraining the number\nof nested entries (or number of multi-attr entries)."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f750dfe825b904164688adeb147950e0e0c4d262","status":"affected","lessThan":"d4c9cc7c47781c6f4fa29d80a1193a8bcd1525bc","versionType":"git"},{"version":"f750dfe825b904164688adeb147950e0e0c4d262","status":"affected","lessThan":"0c02c190bcd9822477038ff2cee10ea584ac1b1d","versionType":"git"},{"version":"f750dfe825b904164688adeb147950e0e0c4d262","status":"affected","lessThan":"6205f7166d2dd14a017a5802c81e5bd1421a8635","versionType":"git"},{"version":"f750dfe825b904164688adeb147950e0e0c4d262","status":"affected","lessThan":"7281b096b072f6c6e30420e3467d738f2e4c4b57","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ethtool/coalesce.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.11","versionType":"semver"},{"version":"6.12.93","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.35","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.12","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ethtool/coalesce.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/d4c9cc7c47781c6f4fa29d80a1193a8bcd1525bc"},{"url":"https://git.kernel.org/stable/c/0c02c190bcd9822477038ff2cee10ea584ac1b1d"},{"url":"https://git.kernel.org/stable/c/6205f7166d2dd14a017a5802c81e5bd1421a8635"},{"url":"https://git.kernel.org/stable/c/7281b096b072f6c6e30420e3467d738f2e4c4b57"}],"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 bug is reached only through the ETHTOOL_MSG_COALESCE_SET generic-netlink ioctl path (ethnl_default_set_doit → ethnl_set_coalesce → ethnl_update_profile), not via remote network packets or physical bus access.\nAC:L - An attacker with CAP_NET_ADMIN can send a crafted netlink message with more than five nested ETHTOOL_A_PROFILE_IRQ_MODERATION attributes and deterministically trigger a heap buffer overflow past the five-entry kmemdup buffer.\nPR:L - ETHTOOL_MSG_COALESCE_SET is gated by GENL_UNS_ADMIN_PERM, which requires CAP_NET_ADMIN in the socket's network namespace user namespace; this capability is obtainable by an unprivileged user via user namespaces (unshare -Urn) or containers granted NET_ADMIN (e.g., hostNetwork pods).\nUI:N - Exploitation requires only the attacker's own ethtool netlink SET_COALESCE request with a malformed profile nest; no action by another user or victim is needed.\nS:U - The vulnerability corrupts kernel heap memory within the same kernel security domain; it does not by itself cross a VM, container, or IOMMU boundary to affect a separate security authority.\nC:H - The out-of-bounds writes past the 120-byte (5 × 24-byte dim_cq_moder) kmalloc allocation can corrupt adjacent slab objects, providing a standard heap-corruption primitive that can be leveraged for arbitrary kernel memory disclosure.\nI:H - The attacker fully controls the overflowed u16 profile fields (usec, pkts, comps) written beyond the allocation boundary, enabling heap metadata or adjacent-object corruption that can be developed into arbitrary kernel write or code execution.\nA:H - Heap corruption from unbounded profile indexing can cause immediate kernel oops/panic during the write or when the corrupted profile is subsequently used by DIM/virtio-net interrupt moderation paths."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:37:54.593Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.12.93"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.18.35"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"7.0.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"7.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-63987","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:34:43.913131Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-787","lang":"en","type":"CWE","description":"CWE-787 Out-of-bounds Write"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T20:18:01.044Z"}}]}}}