Answer in brief
CVE-2026-90203 records a High severity (CVSS 7.1) vulnerability in Squashfs: check block offset is not negative. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=f400e12656ab518be107febfe2315fb1eab5a342 <b169185d5c672b989985c6c2e38cafab2548ba88 || >=f400e12656ab518be107febfe2315fb1eab5a342 <c2a126fca820ae74872da28de68dc74d4595dc4b || >=f400e12656ab518be107febfe2315fb1eab5a342 <95dadf366c117dcdca78a570e6832071deab1ecd || >=f400e12656ab518be107febfe2315fb1eab5a342 <3d2f0cb66c909ea2312cdef465165bb9a3ba2d84 || >=f400e12656ab518be107febfe2315fb1eab5a342 <bbb2218eb072b0a15dc063929200183bd23c2344 || >=f400e12656ab518be107febfe2315fb1eab5a342 <d0a3729d464fcf516416a41cf304c0c92126ee03 || >=f400e12656ab518be107febfe2315fb1eab5a342 <e4afd90bc7bf3dd477970c6c42bdd29ad3fda7fe || >=f400e12656ab518be107febfe2315fb1eab5a342 <e300eb5002925b29be803d2661af07266cfa267e | b169185d5c672b989985c6c2e38cafab2548ba88, c2a126fca820ae74872da28de68dc74d4595dc4b, 95dadf366c117dcdca78a570e6832071deab1ecd, 3d2f0cb66c909ea2312cdef465165bb9a3ba2d84, bbb2218eb072b0a15dc063929200183bd23c2344, d0a3729d464fcf516416a41cf304c0c92126ee03, e4afd90bc7bf3dd477970c6c42bdd29ad3fda7fe, e300eb5002925b29be803d2661af07266cfa267e |
| Linux/Linuxgeneric | 2.6.29 | Not reported |
Published upstream
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 17, 2026
In the Linux kernel, the following vulnerability has been resolved: Squashfs: check block offset is not negative If a negative offset is read off disk (for example the offset into the decompressed fragment block), this will cause squashfs_copy_data() to perform an out of bounds access. Fix by checking if offset is negative, and returning 0. This matches existing behaviour where an offset beyond the block returns 0 bytes copied. To trigger this out of bounds access requires a crafted Squashfs filesystem and CAP_SYS_ADMIN to mount it. Unprivileged users will not be able to mount such a filesystem, but once mounted, an unprivileged user can trigger the out of bounds access by reading the crafted file with the negative offset.
Quoted source text, attributed separately from HOL analysis.