CVE-2026-90203

Last refreshed2026-10-19

Status: UPDATED | Advisory ID: CVE-2026-90203

Key Details

CVE	CVE-2026-90203
CVSS Score / Version	7.1 (High) / CVSS v3.1
Updated	2026-10-19
CVSS Vector	`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H`
CVSS Prose	attack vector is local; attack complexity is low; privileges required is none; user interaction is required; scope is unchanged; confidentiality impact is high; integrity impact is none; availability impact is high.
Affected products	Linux Kernel

Vendor	Product	Affected Versions	Patch Status
Linux	Linux Kernel

Vendor

Product

Affected Versions

Patch Status

Linux

Linux Kernel

Subsystems	OT Supporting Infrastructure
Sectors	All Sectors

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. (NVD)

Monitor Linux's web page for any future patch releases.

Source	Reference
NVD	https://nvd.nist.gov/vuln/detail/CVE-2026-90203
CVE	https://www.cve.org/CVERecord?id=CVE-2026-90203

Source

Reference

NVD

CVE