CVE-2026-90263

In the Linux kernel, the following vulnerability has been resolved: btrfs: check if root is readonly when setting posix acl For a filesystem which has btrfs read-only property set to true, all write operations including acl and xattr should be denied. However, acl can still be set even if btrfs ro property is true. This happens because no function on the set_acl code path checks the root is readonly or not. It was checked in btrfs_setxattr_trans() but got removed in commit 353c2ea735e4 ("btrfs: remove redundant readonly root check in btrfs_setxattr_trans") That commit didn't check if all the callers properly check the root's read-only flag. A previous fix is commit b51111271b03 ("btrfs: check if root is readonly while setting security xattr"). Always check if the root is read-only before performing the set acl operation.

Package Linux Kernel
Published 2026-09-17
Last modified 2026-09-17
Patch available
Yes

Affected versions

Linux kernel versions 5.2 and later are affected. Fixed in 7.2.6, 7.3-rc1 and their respective stable series.

Affected from
≥ 5.2
Fixed in
✓ 7.2.6 7.2.x ✓ 7.3-rc1

References

2 total

Frequently asked questions

  • What is CVE-2026-90263?

    CVE-2026-90263 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 5.2 onward and has been patched in 7.2.6 and 7.3-rc1. CVE-2026-90263 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • Is there a patch available for CVE-2026-90263?

    Yes. CVE-2026-90263 has been patched. Fixed versions include 7.2.6 and 7.3-rc1. If you are running Linux kernel 5.2 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2026-90263 actively exploited?

    No. CVE-2026-90263 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

Back to
All CVEs
View on
NVD / NIST