CVE-2026-28804
MEDIUM5.3EPSS 0.02%pypdf vulnerable to inefficient decoding of ASCIIHexDecode streams
Published: 3/2/2026Modified: 4/28/2026
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.
Affected packages (3)
- Debian/pypdffrom 0
- Debian/pypdf2from 0
- PyPI/pypdffrom 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 |
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
References (7)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-28804
- ADVISORYhttps://security-tracker.debian.org/tracker/CVE-2026-28804
- PATCHhttps://github.com/py-pdf/pypdf
- WEBhttps://github.com/py-pdf/pypdf/commit/648c627d2657447dfb1773412af05a0a5103b98f
- WEBhttps://github.com/py-pdf/pypdf/pull/3666
- WEBhttps://github.com/py-pdf/pypdf/releases/tag/6.7.5
- WEBhttps://github.com/py-pdf/pypdf/security/advisories/GHSA-9m86-7pmv-2852