SB2026051550 - Chunk smuggling in libpng
Published: May 15, 2026
Security Bulletin ID
SB2026051550
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Interpretation Conflict (CVE-ID: CVE-2026-40930)
The vulnerability allows a remote attacker to modify rendered image content or cause a denial of service.
The vulnerability exists due to interpretation conflict in the push-mode APNG parser when processing a crafted APNG image containing an ignored ancillary chunk with an unconsumed chunk body. A remote attacker can send a specially crafted PNG image to modify rendered image content or cause a denial of service.
User interaction is required to open the malicious image, and only push-mode applications using png_process_data are affected.
Remediation
Install update from vendor's website.