{"id":"CVE-2025-39838","state":"PUBLISHED","title":"cifs: prevent NULL pointer dereference in UTF16 conversion","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: prevent NULL pointer dereference in UTF16 conversion\n\nThere can be a NULL pointer dereference bug here. NULL is passed to\n__cifs_sfu_make_node without checks, which passes it unchecked to\ncifs_strndup_to_utf16, which in turn passes it to\ncifs_local_to_utf16_bytes where '*from' is dereferenced, causing a crash.\n\nThis patch adds a check for NULL 'src' in cifs_strndup_to_utf16 and\nreturns NULL early to prevent dereferencing NULL pointer.\n\nFound by Linux Verification Center (linuxtesting.org) with SVACE","publishedAt":"2025-09-19T15:26:13.506Z","updatedAt":"2026-05-12T12:07:26.229Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"41d3f256c6a5e41eb32b87168399c0facd512dc0","status":"affected","lessThan":"1f797f062b5cf13a1c2bcc23285361baaa7c9260","versionType":"git"},{"version":"41d3f256c6a5e41eb32b87168399c0facd512dc0","status":"affected","lessThan":"3c26a8d30ed6b53a52a023ec537dc50a6d34a67a","versionType":"git"},{"version":"41d3f256c6a5e41eb32b87168399c0facd512dc0","status":"affected","lessThan":"70bccd9855dae56942f2b18a08ba137bb54093a0","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/cifs_unicode.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.12","versionType":"semver"},{"version":"6.12.46","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.16.6","status":"unaffected","lessThanOrEqual":"6.16.*","versionType":"semver"},{"version":"6.17","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/cifs_unicode.c"]}],"references":["https://git.kernel.org/stable/c/1f797f062b5cf13a1c2bcc23285361baaa7c9260","https://git.kernel.org/stable/c/3c26a8d30ed6b53a52a023ec537dc50a6d34a67a","https://git.kernel.org/stable/c/70bccd9855dae56942f2b18a08ba137bb54093a0","https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html","https://cert-portal.siemens.com/productcert/html/ssa-032379.html"],"weaknesses":[],"ingestedAt":"2026-10-29T20:09:09.358Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/39xxx/CVE-2025-39838.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-39838","state":"PUBLISHED","datePublished":"2025-09-19T15:26:13.506Z","dateUpdated":"2026-05-12T12:07:26.229Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-04-16T07:20:57.141Z"},"containers":{"cna":{"title":"cifs: prevent NULL pointer dereference in UTF16 conversion","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: prevent NULL pointer dereference in UTF16 conversion\n\nThere can be a NULL pointer dereference bug here. NULL is passed to\n__cifs_sfu_make_node without checks, which passes it unchecked to\ncifs_strndup_to_utf16, which in turn passes it to\ncifs_local_to_utf16_bytes where '*from' is dereferenced, causing a crash.\n\nThis patch adds a check for NULL 'src' in cifs_strndup_to_utf16 and\nreturns NULL early to prevent dereferencing NULL pointer.\n\nFound by Linux Verification Center (linuxtesting.org) with SVACE"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"41d3f256c6a5e41eb32b87168399c0facd512dc0","status":"affected","lessThan":"1f797f062b5cf13a1c2bcc23285361baaa7c9260","versionType":"git"},{"version":"41d3f256c6a5e41eb32b87168399c0facd512dc0","status":"affected","lessThan":"3c26a8d30ed6b53a52a023ec537dc50a6d34a67a","versionType":"git"},{"version":"41d3f256c6a5e41eb32b87168399c0facd512dc0","status":"affected","lessThan":"70bccd9855dae56942f2b18a08ba137bb54093a0","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/cifs_unicode.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.12","versionType":"semver"},{"version":"6.12.46","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.16.6","status":"unaffected","lessThanOrEqual":"6.16.*","versionType":"semver"},{"version":"6.17","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/cifs_unicode.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/1f797f062b5cf13a1c2bcc23285361baaa7c9260"},{"url":"https://git.kernel.org/stable/c/3c26a8d30ed6b53a52a023ec537dc50a6d34a67a"},{"url":"https://git.kernel.org/stable/c/70bccd9855dae56942f2b18a08ba137bb54093a0"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T21:37:25.302Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.12.46"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.16.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.17"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2025-11-03T17:43:52.863Z"}},{"affected":[{"vendor":"Siemens","product":"SIMATIC CN 4100","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"V5.0","versionType":"custom"}]}],"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-032379.html"}],"providerMetadata":{"shortName":"siemens-SADP","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","dateUpdated":"2026-05-12T12:07:26.229Z"},"x_adpType":"supplier"}]}}}