medium5.3
CVE-2026-41168
pypdf has long runtimes for wrong size values in cross-reference and object streams
Impact
pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.1 can craft a PDF which leads to long runtimes. This requires cross-reference streams with wrong large `/Size` values or object streams with wrong large `/N` values. This has been fixed in pypdf 6.10.1. As a workaround, one may apply the changes from the patch manually.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| pip | pypdf | < 6.10.1 | 6.10.1 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Pypdf Project | Pypdf | before 6.10.1 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-jj6c-8h6c-hppx
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-jj6c-8h6c-hppx
- https://github.com/py-pdf/pypdf/pull/3733
- https://github.com/py-pdf/pypdf/releases/tag/6.10.1
- https://nvd.nist.gov/vuln/detail/CVE-2026-41168
- https://github.com/py-pdf/pypdf/commit/62338e9d36419cf193ccec7331784f45df1d70b3