{"id":"CVE-2026-64522","state":"PUBLISHED","title":"net/mlx5e: Fix eswitch mode block underflow on IPsec acquire SA","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: Fix eswitch mode block underflow on IPsec acquire SA\n\nmlx5e_xfrm_add_state() handles acquire-flow temporary SAs by allocating\nsoftware state and skipping hardware offload setup.\n\nThat path jumps to the common success label before taking the eswitch mode\nblock. After tunnel-mode validation was moved earlier, the common success\nlabel unconditionally calls mlx5_eswitch_unblock_mode(). For acquire SAs,\nthis decrements esw->offloads.num_block_mode without a matching increment.\n\nReturn directly after installing the acquire SA offload handle, so only the\npaths that successfully called mlx5_eswitch_block_mode() call the matching\nunblock.","publishedAt":"2026-07-25T09:14:47.404Z","updatedAt":"2026-10-19T20:48:37.735Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"22239eb258bc1e6ccdb2d3502fce1cc2b2a88386","status":"affected","lessThan":"b5bd4249e430f5963d559708ee96a671716d2400","versionType":"git"},{"version":"22239eb258bc1e6ccdb2d3502fce1cc2b2a88386","status":"affected","lessThan":"ecafd8284e527666e83261e6e57a7c7341d591cb","versionType":"git"},{"version":"22239eb258bc1e6ccdb2d3502fce1cc2b2a88386","status":"affected","lessThan":"abe003b33223ff33552f291644bf35d9c2f992fb","versionType":"git"},{"version":"993c4ba71596c30418ba5a0ddcf4f9c2f431466a","status":"affected","versionType":"git"},{"version":"6.17.4","status":"affected","lessThan":"6.18","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.18","versionType":"semver"},{"version":"6.18.34","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.11","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":["drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.c"]}],"references":["https://git.kernel.org/stable/c/b5bd4249e430f5963d559708ee96a671716d2400","https://git.kernel.org/stable/c/ecafd8284e527666e83261e6e57a7c7341d591cb","https://git.kernel.org/stable/c/abe003b33223ff33552f291644bf35d9c2f992fb"],"weaknesses":["CWE-190"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/64xxx/CVE-2026-64522.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64522","state":"PUBLISHED","datePublished":"2026-07-25T09:14:47.404Z","dateUpdated":"2026-10-19T20:48:37.735Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T15:36:31.794Z"},"containers":{"cna":{"title":"net/mlx5e: Fix eswitch mode block underflow on IPsec acquire SA","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: Fix eswitch mode block underflow on IPsec acquire SA\n\nmlx5e_xfrm_add_state() handles acquire-flow temporary SAs by allocating\nsoftware state and skipping hardware offload setup.\n\nThat path jumps to the common success label before taking the eswitch mode\nblock. After tunnel-mode validation was moved earlier, the common success\nlabel unconditionally calls mlx5_eswitch_unblock_mode(). For acquire SAs,\nthis decrements esw->offloads.num_block_mode without a matching increment.\n\nReturn directly after installing the acquire SA offload handle, so only the\npaths that successfully called mlx5_eswitch_block_mode() call the matching\nunblock."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"22239eb258bc1e6ccdb2d3502fce1cc2b2a88386","status":"affected","lessThan":"b5bd4249e430f5963d559708ee96a671716d2400","versionType":"git"},{"version":"22239eb258bc1e6ccdb2d3502fce1cc2b2a88386","status":"affected","lessThan":"ecafd8284e527666e83261e6e57a7c7341d591cb","versionType":"git"},{"version":"22239eb258bc1e6ccdb2d3502fce1cc2b2a88386","status":"affected","lessThan":"abe003b33223ff33552f291644bf35d9c2f992fb","versionType":"git"},{"version":"993c4ba71596c30418ba5a0ddcf4f9c2f431466a","status":"affected","versionType":"git"},{"version":"6.17.4","status":"affected","lessThan":"6.18","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.18","versionType":"semver"},{"version":"6.18.34","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.11","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":["drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/b5bd4249e430f5963d559708ee96a671716d2400"},{"url":"https://git.kernel.org/stable/c/ecafd8284e527666e83261e6e57a7c7341d591cb"},{"url":"https://git.kernel.org/stable/c/abe003b33223ff33552f291644bf35d9c2f992fb"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - A remote TCP SYN can cause the kernel to route a SYN-ACK through an administrator-configured outbound mlx5 IPsec policy, reaching xfrm_state_find() and the vulnerable acquire-SA callback.\nAC:L - Once the affected packet-offload policy is deployed without a matching SA, the first matching flow deterministically performs the unmatched decrement; no race must be won.\nPR:N - The remote peer needs no credentials or capabilities; configuring the mlx5 IPsec policy is a deployment prerequisite, not an attacker privilege.\nUI:R - The highest-impact stale-object path requires an administrator to request an eswitch mode transition after the attacker has cancelled the live mode-block reference.\nS:U - The resulting corruption affects the same host kernel and mlx5 device security authority, without crossing a VM, IOMMU, or sandbox boundary.\nC:H - The incorrectly permitted mode transition frees mlx5 IPsec structures while XFRM policies retain references to them, creating subsequent use-after-free callbacks capable of exposing kernel memory.\nI:H - The stale policy and flow-table references can be reclaimed and attacker-influenced, making the resulting kernel use-after-free potentially exploitable for arbitrary writes or control-flow hijacking.\nA:H - Mode-transition teardown or later automatic policy expiration can dereference freed IPsec and flow-rule objects, causing a kernel warning, oops, or panic."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:42:35.590Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"6.18.34"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"7.0.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18","versionEndExcluding":"7.1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17.4"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-64522","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:41:33.468596Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-190","lang":"en","type":"CWE","description":"CWE-190 Integer Overflow or Wraparound"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T20:48:37.735Z"}}]}}}