{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-40287","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-04-16T07:20:57.184Z","datePublished":"2025-12-06T21:51:13.328Z","dateUpdated":"2026-05-11T21:46:25.955Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T21:46:25.955Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nexfat: fix improper check of dentry.stream.valid_size\n\nWe found an infinite loop bug in the exFAT file system that can lead to a\nDenial-of-Service (DoS) condition. When a dentry in an exFAT filesystem is\nmalformed, the following system calls — SYS_openat, SYS_ftruncate, and\nSYS_pwrite64 — can cause the kernel to hang.\n\nRoot cause analysis shows that the size validation code in exfat_find()\ndoes not check whether dentry.stream.valid_size is negative. As a result,\nthe system calls mentioned above can succeed and eventually trigger the DoS\nissue.\n\nThis patch adds a check for negative dentry.stream.valid_size to prevent\nthis vulnerability."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/exfat/namei.c"],"versions":[{"version":"11a347fb6cef62ce47e84b97c45f2b2497c7593b","lessThan":"6c627bcc1896ba62ec793d0c00da74f3c93ce3ad","status":"affected","versionType":"git"},{"version":"11a347fb6cef62ce47e84b97c45f2b2497c7593b","lessThan":"204b1b02ee018ba52ad2ece21fe3a8643d66a1b2","status":"affected","versionType":"git"},{"version":"11a347fb6cef62ce47e84b97c45f2b2497c7593b","lessThan":"82ebecdc74ff555daf70b811d854b1f32a296bea","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/exfat/namei.c"],"versions":[{"version":"6.8","status":"affected"},{"version":"0","lessThan":"6.8","status":"unaffected","versionType":"semver"},{"version":"6.12.59","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.17.9","lessThanOrEqual":"6.17.*","status":"unaffected","versionType":"semver"},{"version":"6.18","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.8","versionEndExcluding":"6.12.59"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.8","versionEndExcluding":"6.17.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.8","versionEndExcluding":"6.18"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/6c627bcc1896ba62ec793d0c00da74f3c93ce3ad"},{"url":"https://git.kernel.org/stable/c/204b1b02ee018ba52ad2ece21fe3a8643d66a1b2"},{"url":"https://git.kernel.org/stable/c/82ebecdc74ff555daf70b811d854b1f32a296bea"}],"title":"exfat: fix improper check of dentry.stream.valid_size","x_generator":{"engine":"bippy-1.2.0"}}}}