CVE-2026-40930 | BDVDB-2026-338069 Detail

pnggrouplibpng

Description#

LIBPNG is a reference library for use in applications that process PNG (Portable Network Graphics) raster image files. In version 1.8.0, three inter-frame chunk discard paths in the push-mode APNG parser clear the chunk-header flag without consuming the chunk body and CRC, allowing attacker-controlled bytes inside an ignored ancillary chunk to be reinterpreted as a fresh chunk header on the next call to `png_process_data`. Commit faf06924688b62d7c1654b5ceddedbde66ffadb4 fixes the issue.

Impact#

Per CVSS v3.1: confidentiality impact none, integrity impact low, availability impact low. Attack vector: network.

Weaknesses#

CWE-436 Interpretation Conflict

References#

Exploit#

No public exploit known

History#

Version 12026-06-04Record published in the CVE List.

Published

Published: 2026-06-04
Last modified: 2026-06-04

Vendor information

Vendor: pnggroup
Product: libpng

All pnggroup vulnerabilities

Score

5.4 Medium

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 10.3.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Not classified

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
= 1.8.0
Fixed
Not stated

Scoring System

CVSS v4.0

Not available

CVSS v3.1

5.4 Medium

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Privileges Required	None
User Interaction	Required
Scope	Unchanged
Confidentiality	None
Integrity	Low
Availability	Low

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).