Buffer overflow in Qpdf Project

CVE-2021-36978

QPDF 9.x through 9.1.1 and 10.x through 10.0.4 has a heap-based buffer overflow in Pl_ASCII85Decoder::write (called from Pl_AES_PDF::flush and Pl_AES_PDF::finish) when a certain downstream write fails.

Vulnerability class: Buffer Overflow

EPSS: 0.013 (66.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-36978?
CVE-2021-36978 is a medium-severity vulnerability in Qpdf Project, classified under Out-of-bounds Write. CVSS score: 5.5/10. Published 2021-07-20.
How severe is CVE-2021-36978?
Medium severity. CVSS v3 base score is 5.5 out of 10.
Is CVE-2021-36978 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.