CVE-2026-27628
HIGH7.5EPSS 0.06%pypdf has a possible infinite loop when loading circular /Prev entries in cross-reference streams
Published: 2/25/2026Modified: 4/28/2026
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.7.2, an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires reading the file. This has been fixed in pypdf 6.7.2. As a workaround, one may apply the patch manually.
Affected packages (3)
- Debian/pypdffrom 0
- Debian/pypdf2from 0
- PyPI/pypdffrom 0, < 6.7.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U |
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
References (6)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-27628
- ADVISORYhttps://security-tracker.debian.org/tracker/CVE-2026-27628
- PATCHhttps://github.com/py-pdf/pypdf
- WEBhttps://github.com/py-pdf/pypdf/commit/f0a462d36971cf077d74492a348d0d06fd60ea4d
- WEBhttps://github.com/py-pdf/pypdf/issues/3654
- WEBhttps://github.com/py-pdf/pypdf/security/advisories/GHSA-2rw7-x74f-jg35