{"id":"CVE-2026-72356","state":"PUBLISHED","title":"cifs: Fix missing credit release on failure in cifs_issue_read()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: Fix missing credit release on failure in cifs_issue_read()\n\nFix missing release of credits in the failure path in cifs_issue_read()\nlest retrying the subreq just overwrites the credits value.","publishedAt":"2026-08-15T05:55:57.464Z","updatedAt":"2026-08-17T05:43:14.352Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"69c3c023af25edb5433a2db824d3e7cc328f0183","status":"affected","lessThan":"b9ee1f0347bf56d019ca28ddff090234bb45b05c","versionType":"git"},{"version":"69c3c023af25edb5433a2db824d3e7cc328f0183","status":"affected","lessThan":"86652704a7fd41a5a8459027e08640bbd1952826","versionType":"git"},{"version":"69c3c023af25edb5433a2db824d3e7cc328f0183","status":"affected","lessThan":"3a303f985c6bec8787c2ad4a16b39c14c5bcd765","versionType":"git"},{"version":"69c3c023af25edb5433a2db824d3e7cc328f0183","status":"affected","lessThan":"c16b8c4cfb4fe2244cc33e469a93c1ab8684146b","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/file.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.10","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/file.c"]}],"references":["https://git.kernel.org/stable/c/b9ee1f0347bf56d019ca28ddff090234bb45b05c","https://git.kernel.org/stable/c/86652704a7fd41a5a8459027e08640bbd1952826","https://git.kernel.org/stable/c/3a303f985c6bec8787c2ad4a16b39c14c5bcd765","https://git.kernel.org/stable/c/c16b8c4cfb4fe2244cc33e469a93c1ab8684146b"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/72xxx/CVE-2026-72356.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72356","state":"PUBLISHED","datePublished":"2026-08-15T05:55:57.464Z","dateUpdated":"2026-08-17T05:43:14.352Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-09T03:40:39.921Z"},"containers":{"cna":{"title":"cifs: Fix missing credit release on failure in cifs_issue_read()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: Fix missing credit release on failure in cifs_issue_read()\n\nFix missing release of credits in the failure path in cifs_issue_read()\nlest retrying the subreq just overwrites the credits value."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"69c3c023af25edb5433a2db824d3e7cc328f0183","status":"affected","lessThan":"b9ee1f0347bf56d019ca28ddff090234bb45b05c","versionType":"git"},{"version":"69c3c023af25edb5433a2db824d3e7cc328f0183","status":"affected","lessThan":"86652704a7fd41a5a8459027e08640bbd1952826","versionType":"git"},{"version":"69c3c023af25edb5433a2db824d3e7cc328f0183","status":"affected","lessThan":"3a303f985c6bec8787c2ad4a16b39c14c5bcd765","versionType":"git"},{"version":"69c3c023af25edb5433a2db824d3e7cc328f0183","status":"affected","lessThan":"c16b8c4cfb4fe2244cc33e469a93c1ab8684146b","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/file.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.10","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.10","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/file.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/b9ee1f0347bf56d019ca28ddff090234bb45b05c"},{"url":"https://git.kernel.org/stable/c/86652704a7fd41a5a8459027e08640bbd1952826"},{"url":"https://git.kernel.org/stable/c/3a303f985c6bec8787c2ad4a16b39c14c5bcd765"},{"url":"https://git.kernel.org/stable/c/c16b8c4cfb4fe2244cc33e469a93c1ab8684146b"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - The bug is in the CIFS/SMB client read path reached over TCP/445 when netfs issues reads; a malicious or compromised remote SMB server can provoke replayable async_readv failures (-EAGAIN/-ECONNABORTED) after credits are reserved, matching prior client-side CIFS credit CVEs scored as Network.\nAC:L - The remote server controls both sides of the retry: it can reset the connection or force reconnects to return replayable errors, and netfs reissues the same subrequest deterministically; no race or memory-layout condition outside attacker control is required.\nPR:N - The attacker is the remote SMB peer and needs no account, credentials, or local privileges on the victim; exploitation occurs during normal read/writeback I/O on an already-established CIFS mount (fstab, autofs, Azure Files, enterprise NAS).\nUI:N - Once a CIFS mount exists, the server triggers the flaw by its responses to client-initiated reads with no further victim interaction; mounting is a deployment precondition, not an action required at exploit time per kernel CNA convention for client filesystem bugs.\nS:U - Impact is confined to SMB credit/in_flight accounting and I/O scheduling within the client kernel; it does not cross VM, IOMMU, or sandbox security boundaries.\nC:N - The flaw leaks SMB protocol credits and misaccounts counters; it does not read or disclose kernel memory, user data, or pointers, and provides no information-disclosure primitive.\nI:N - No memory corruption, type confusion, or arbitrary write occurs; the only effect is permanently losing credits from the server pool when a failed read subrequest is retried without releasing them first.\nA:H - Each leaked credit permanently depletes server->credits; repeated retries exhaust the pool until smb2_wait_mtu_credits blocks all CIFS I/O on that connection in uninterruptible waits, causing system-wide hang/DoS for processes using the mount."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T05:43:14.352Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"6.12.97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}