{"id":"CVE-2026-46185","state":"PUBLISHED","title":"smb/client: fix out-of-bounds read in symlink_data()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb/client: fix out-of-bounds read in symlink_data()\n\nSince smb2_check_message() returns success without length validation for\nthe symlink error response, in symlink_data() it is possible for\niov->iov_len to be smaller than sizeof(struct smb2_err_rsp). If the buffer\nonly contains the base SMB2 header (64 bytes), accessing\nerr->ErrorContextCount (at offset 66) or err->ByteCount later in\nsymlink_data() will cause an out-of-bounds read.","publishedAt":"2026-05-28T09:36:39.318Z","updatedAt":"2026-10-19T19:36:54.280Z","severity":{"score":9.1,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"2be11faf79e49fb8250a181ff0b4d2b2f084af83","versionType":"git"},{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"ef6495d4df6e7af8f3de67e65150881c880f696c","versionType":"git"},{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"15dc0a4de743a1aaa7b859b3aea79f08c695396c","versionType":"git"},{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"b8c8a704f0bc133deb171f6aeb6f3a684203e212","versionType":"git"},{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"b9561402489d41149f63e001a74384863b7b30a6","versionType":"git"},{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"d62b8d236fab503c6fec1d3e9a38bea71feaca20","versionType":"git"},{"version":"2d046892a493d9760c35fdaefc3017f27f91b621","status":"affected","versionType":"git"},{"version":"6.0.16","status":"affected","lessThan":"6.1","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/smb2misc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.1","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.140","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.88","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.30","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.7","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":["fs/smb/client/smb2misc.c"]}],"references":["https://git.kernel.org/stable/c/2be11faf79e49fb8250a181ff0b4d2b2f084af83","https://git.kernel.org/stable/c/ef6495d4df6e7af8f3de67e65150881c880f696c","https://git.kernel.org/stable/c/15dc0a4de743a1aaa7b859b3aea79f08c695396c","https://git.kernel.org/stable/c/b8c8a704f0bc133deb171f6aeb6f3a684203e212","https://git.kernel.org/stable/c/b9561402489d41149f63e001a74384863b7b30a6","https://git.kernel.org/stable/c/d62b8d236fab503c6fec1d3e9a38bea71feaca20","https://cert-portal.siemens.com/productcert/html/ssa-784472.html"],"weaknesses":["CWE-125"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/46xxx/CVE-2026-46185.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-46185","state":"PUBLISHED","datePublished":"2026-05-28T09:36:39.318Z","dateUpdated":"2026-10-19T19:36:54.280Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-05-13T15:03:33.103Z"},"containers":{"cna":{"title":"smb/client: fix out-of-bounds read in symlink_data()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb/client: fix out-of-bounds read in symlink_data()\n\nSince smb2_check_message() returns success without length validation for\nthe symlink error response, in symlink_data() it is possible for\niov->iov_len to be smaller than sizeof(struct smb2_err_rsp). If the buffer\nonly contains the base SMB2 header (64 bytes), accessing\nerr->ErrorContextCount (at offset 66) or err->ByteCount later in\nsymlink_data() will cause an out-of-bounds read."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"2be11faf79e49fb8250a181ff0b4d2b2f084af83","versionType":"git"},{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"ef6495d4df6e7af8f3de67e65150881c880f696c","versionType":"git"},{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"15dc0a4de743a1aaa7b859b3aea79f08c695396c","versionType":"git"},{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"b8c8a704f0bc133deb171f6aeb6f3a684203e212","versionType":"git"},{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"b9561402489d41149f63e001a74384863b7b30a6","versionType":"git"},{"version":"76894f3e2f71177747b8b4763fb180e800279585","status":"affected","lessThan":"d62b8d236fab503c6fec1d3e9a38bea71feaca20","versionType":"git"},{"version":"2d046892a493d9760c35fdaefc3017f27f91b621","status":"affected","versionType":"git"},{"version":"6.0.16","status":"affected","lessThan":"6.1","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/smb2misc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.1","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.140","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.88","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.30","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.7","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":["fs/smb/client/smb2misc.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/2be11faf79e49fb8250a181ff0b4d2b2f084af83"},{"url":"https://git.kernel.org/stable/c/ef6495d4df6e7af8f3de67e65150881c880f696c"},{"url":"https://git.kernel.org/stable/c/15dc0a4de743a1aaa7b859b3aea79f08c695396c"},{"url":"https://git.kernel.org/stable/c/b8c8a704f0bc133deb171f6aeb6f3a684203e212"},{"url":"https://git.kernel.org/stable/c/b9561402489d41149f63e001a74384863b7b30a6"},{"url":"https://git.kernel.org/stable/c/d62b8d236fab503c6fec1d3e9a38bea71feaca20"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","baseScore":9.1,"baseSeverity":"CRITICAL"},"scenarios":[{"lang":"en","value":"AV:N - The vulnerability is in the SMB *client*, triggered by a crafted symlink error response from a remote (malicious, compromised, or MITM) SMB server over TCP/445; it processes attacker-controlled data from a remote network peer.\nAC:L - A malicious server can deterministically return a CREATE response with STATUS_STOPPED_ON_SYMLINK and len < calc_len (e.g., only the 64-byte base header), reliably reaching symlink_data() with no race or attacker-uncontrolled condition.\nPR:N - The attacker is the remote SMB server; it requires no credentials or privileges on the victim client to send the malformed response, which is parsed during normal open/error handling.\nUI:N - Once a share is mounted (e.g., persistent fstab/autofs mount to a compromised or MITM'd server), routine file access makes the server return the crafted symlink error with no additional victim action required per exploit.\nS:U - The out-of-bounds read stays within the client kernel's own memory and security authority; no privilege or sandbox boundary is crossed.\nC:H - An out-of-bounds read of adjacent kernel heap memory; in this same symlink-parse path (cf. CVE-2026-31613) OOB bytes are UTF-16-decoded into the symlink target and returned to userspace via readlink(2).\nI:N - The flaw is purely an out-of-bounds read of the error response buffer; it does not modify kernel memory.\nA:H - Reading past the message bounds can dereference invalid/unmapped memory and oops the client kernel, causing a denial of service."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:30:18.630Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.1.175"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.6.140"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.12.88"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"6.18.30"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"7.0.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1","versionEndExcluding":"7.1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0.16"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"*","versionType":"custom"}]}],"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html"}],"providerMetadata":{"shortName":"siemens-SADP","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","dateUpdated":"2026-10-15T01:21:09.431Z"},"x_adpType":"supplier"},{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-46185","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-10-16T15:20:54.231422Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-125","lang":"en","type":"CWE","description":"CWE-125 Out-of-bounds Read"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T19:36:54.280Z"}}]}}}