GHSA-2rw7-x74f-jg35

pypdf has a possible infinite loop when loading circular /Prev entries in cross-reference streams

Source: GitHub Advisory Database (reviewed) Low CVE-2026-27628

Packages

Ecosystem	Package	Affected	Fixed in
PyPI	pypdf	< 6.7.2	6.7.2

Details

As written in the advisory (Markdown source, shown as plain text).

### Impact An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires reading the file. ### Patches This has been fixed in [pypdf==6.7.2](https://github.com/py-pdf/pypdf/releases/tag/6.7.2). ### Workarounds If users cannot upgrade yet, consider applying the changes from PR [#3655](https://github.com/py-pdf/pypdf/pull/3655).

References

External links from the advisory. They lead to third-party sites.

https://github.com/py-pdf/pypdf/security/advisories/GHSA-2rw7-x74f-jg35 web
https://nvd.nist.gov/vuln/detail/CVE-2026-27628 advisory
https://github.com/py-pdf/pypdf/issues/3654 web
https://github.com/py-pdf/pypdf/commit/f0a462d36971cf077d74492a348d0d06fd60ea4d web
https://github.com/py-pdf/pypdf package