PT-2026-61124 · Linux · Linux Kernel

CVE-2026-63808 · Published 2026-07-19 · Updated 2026-07-19

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A use-after-free issue exists in the exfat find dir entry() function. The problem occurs when a buffer head obtained from exfat get dentry() is released using brelse(bh) before the TYPE EXTEND branch reads the directory entry through the ep pointer, which points to bh->b data. Because the reference is dropped, the underlying page backing the data may no longer be valid when exfat extract uni name() is called, leading to a potential kernel fault.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Related Identifiers

CVE-2026-63808

Affected Products

Linux Kernel

References · 10

• https://nvd.nist.gov/vuln/detail/CVE-2026-63808 · Security Note
• https://twitter.com/VulmonFeeds/status/2078912517670097011 · Twitter Post
• https://git.kernel.org/stable/c/e6f1a11cfb808441a43ffae9b476cc135732cd27 · Note
• https://git.kernel.org/stable/c/8e0abc17fbd7e305802e84fe98b4950d50f9c433 · Note
• https://git.kernel.org/stable/c/e48f413c2815787b8cade2795e194e3c4cd782ef · Note
• https://git.kernel.org/stable/c/adfacfbaeae2cb760f492357cc36b41f84ef7f86 · Note
• https://git.kernel.org/stable/c/708b97e792945d3e4653939fd3405d71a61ad065 · Note
• https://git.kernel.org/stable/c/3f5f8ee9917cc2b9076ac533492d8a200edcabb8 · Note
• https://git.kernel.org/stable/c/4d101016d5e587f820b3ae2d5bb6770d86342649 · Note
• https://git.kernel.org/stable/c/06c4e1e9967d332ac33ba38b7819851089ff9359 · Note