CVE-2026-28804
pypdf vulnerable to inefficient decoding of ASCIIHexDecode streams
EPSS 0.40%
Description
pypdf is a free and open-source pure-python PDF library. Prior to version 6.7.5, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the /ASCIIHexDecode filter. This issue has been patched in version 6.7.5.
How to fix CVE-2026-28804
To remediate CVE-2026-28804, upgrade the affected package to a fixed version below.
- PyPI/pypdf—upgrade to 6.7.5 or later
- PyPI/pypdf—upgrade to 6.7.5 or later
Is CVE-2026-28804 being exploited?
Low — EPSS is 0.4%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 6.7.5
- from 0, < 6.7.5
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |