Bug 2502181 (CVE-2026-53369)

Summary: CVE-2026-53369 kernel: udf: reject descriptors with oversized CRC length
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in the Linux kernel's Universal Disk Format (UDF) filesystem. A remote attacker could craft a malicious UDF image with an oversized Cyclic Redundancy Check (CRC) length. This could allow the attacker to bypass the integrity validation of UDF descriptors, leading to the acceptance of potentially corrupted or malicious data based on a weak checksum.
 Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-07-19 10:01:44 UTC 
In the Linux kernel, the following vulnerability has been resolved:

udf: reject descriptors with oversized CRC length

udf_read_tagged() skips CRC verification when descCRCLength +
sizeof(struct tag) exceeds the block size.  A crafted UDF image can
set descCRCLength to an oversized value to bypass CRC validation
entirely; the descriptor is then accepted based solely on the 8-bit
tag checksum, which is trivially recomputable.

Reject such descriptors instead of silently accepting them.  A
legitimate single-block descriptor should never have a CRC length that
exceeds the block.
Comment 1 Keith Grant 2026-07-20 12:44:03 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026071918-CVE-2026-53369-8633@gregkh/T