CVE intelligence

CVE-2026-80638

Vulnerability intelligence

Published Aug 28, 2026Sources checked Oct 8, 2026

8.8HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-80638 and is rated High severity with a CVSS score of 8.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

CISA KEVNot listedBased on the latest collected catalog

EPSS0.5%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-80638?

In the Linux kernel, the following vulnerability has been resolved:

ocfs2: fix out-of-bounds write in ocfs2_remove_refcount_extent

[BUG] Unlinking a refcounted file whose refcount tree has leaf blocks triggers a fortify panic due to an out-of-bounds write.

[CAUSE] When the last leaf block is removed from a refcount tree, ocfs2_remove_refcount_extent() converts the root back to leaf mode with a bulk memset on &rb->rf_records. rf_records sits in an anonymous union with rf_list. rf_list.l_tree_depth aliases rf_records.rl_count, and is 0 for a single-level tree.

With rl_count equal to 0, the memset writes past the 16-byte declared size of rf_records, which the fortify checker catches.

[FIX] Replace the bulk memset on &rb->rf_records with a correctly-bounded memset on rl_recs[] alone, after setting rl_count to the correct value.

Source: NVD