CVE-2026-40930: LIBPNG: Chunk smuggling in push-mode APNG parser via unconsumed chunk body
CSIRTS triage
- What
- Chunk smuggling in the push-mode APNG parser via an unconsumed chunk body.
- Who is affected
- Users of libpng.
- Urgency
- Remediation is medium due to the moderate severity and lack of exploitation reports.
- Action
- Update to the latest version of libpng.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40930
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-409300.20% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 10% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-40930 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- medium[UPDATE] [medium] libpng: Vulnerability enables denial of servicecert-bund
- unknownUSN-8639-1: libpng vulnerabilitiesubuntu
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