{"id":"CVE-2026-90203","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nSquashfs: check block offset is not negative\n\nIf a negative offset is read off disk (for example the offset into the\ndecompressed fragment block), this will cause squas…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nSquashfs: check block offset is not negative\n\nIf a negative offset is read off disk (for example the offset into the\ndecompressed fragment block), this will cause squas…","severity":"high","cvss":7.1,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H","vendor":"Linux","product":"Linux","affected":["Linux >= f400e12656ab518be107febfe2315fb1eab5a342 < b169185d5c672b989985c6c2e38cafab2548ba88","Linux >= f400e12656ab518be107febfe2315fb1eab5a342 < c2a126fca820ae74872da28de68dc74d4595dc4b","Linux >= f400e12656ab518be107febfe2315fb1eab5a342 < 95dadf366c117dcdca78a570e6832071deab1ecd","Linux >= f400e12656ab518be107febfe2315fb1eab5a342 < 3d2f0cb66c909ea2312cdef465165bb9a3ba2d84","Linux >= f400e12656ab518be107febfe2315fb1eab5a342 < bbb2218eb072b0a15dc063929200183bd23c2344","Linux >= f400e12656ab518be107febfe2315fb1eab5a342 < d0a3729d464fcf516416a41cf304c0c92126ee03","Linux >= f400e12656ab518be107febfe2315fb1eab5a342 < e4afd90bc7bf3dd477970c6c42bdd29ad3fda7fe","Linux >= f400e12656ab518be107febfe2315fb1eab5a342 < e300eb5002925b29be803d2661af07266cfa267e","Linux 2.6.29"],"published":"2026-09-17","updated":"2026-09-18","sourceUpdated":"2026-09-18T18:17:46.120","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-90203","references":[{"url":"https://git.kernel.org/stable/c/3d2f0cb66c909ea2312cdef465165bb9a3ba2d84","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/95dadf366c117dcdca78a570e6832071deab1ecd","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b169185d5c672b989985c6c2e38cafab2548ba88","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/bbb2218eb072b0a15dc063929200183bd23c2344","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c2a126fca820ae74872da28de68dc74d4595dc4b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d0a3729d464fcf516416a41cf304c0c92126ee03","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e300eb5002925b29be803d2661af07266cfa267e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e4afd90bc7bf3dd477970c6c42bdd29ad3fda7fe","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"epss":0.00176,"epssPercentile":0.06377,"ingestedAt":"2026-09-17T16:21:47.860Z","slug":"CVE-2026-90203","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nSquashfs: check block offset is not negative\n\nIf a negative offset is read off disk (for example the offset into the\ndecompressed fragment block), this will cause squashfs_copy_data() to\nperform an out of bounds access.\n\nFix by checking if offset is negative, and returning 0.  This matches\nexisting behaviour where an offset beyond the block returns 0 bytes\ncopied.\n\nTo trigger this out of bounds access requires a crafted Squashfs\nfilesystem and CAP_SYS_ADMIN to mount it.  Unprivileged users will not be\nable to mount such a filesystem, but once mounted, an unprivileged user\ncan trigger the out of bounds access by reading the crafted file with the\nnegative offset.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":207173,"id":"CVE-2026-90203","ts":1789757338553,"field":"cvss","old":null,"new":"7.1"},{"seq":207172,"id":"CVE-2026-90203","ts":1789757338553,"field":"severity","old":"none","new":"high"}]}