Review reviewHigh

CVE-2026-64027

Linux

In the Linux kernel, the following vulnerability has been resolved: net: shaper: rework the VALID marking (again) Recent commit changed the semantics from NOT_VALID to VALID. I didn't realize that the flags are not stored atomically with the entry in XArray. There's still a race of reader observing a VALID mark for a slot, getting interrupted, writer replacing the entry with a different one, reader continuing, fetching the entry which is now a different pointer than the pointer for which VALID was meant. The biggest consequence of this is that we may see a UAF since net_shaper_rollback() as...

CVSS: 7.8
EPSS: -
CISA KEV: Not listed
Published: 2026.07.20

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability-

Technical severityCVSS 7.8

Vulnerability overview

Affected product and versions

Product: Linux
Affected versions: >= 93954b40f6a4fc43226c01a15b02732f884500f1 < 2417df5e7bb4184b9d3a2988036bf2c46e594545, >= 93954b40f6a4fc43226c01a15b02732f884500f1 < 96ea960dd40fd55302e0fd755176f26a95e6a50c, >= 93954b40f6a4fc43226c01a15b02732f884500f1 < b8d7519352ba8c6df83259295d4a3bad093cae90, >= 6.13
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that Linux and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE: Not available