py-pdf/pypdf · Security
pypdf: Possible long runtimes for zero-only width values in cross-reference streamsuntimes for zero-only width values in cross-reference streams
- GHSA ID
- GHSA-248m-82v9-q6g6
- CVE ID
- CVE-2026-48156
- Severity
- medium
- Published
- Updated
- CVSS
- 3.3 · CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
- CVSS v3
- 3.3 · CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
- CVSS v4
- 5.1 · CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Description
Impact
An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires cross-reference streams with /W [0 0 0] values and large /Size values.
Patches
This has been fixed in pypdf==6.12.0.
Workarounds
If developers are unable to upgrade their apps immediately, they should consider applying the changes from PR #3791.
CWEs
- CWE-834 · Excessive Iteration
References
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-248m-82v9-q6g6 ↗
- https://nvd.nist.gov/vuln/detail/CVE-2026-48156 ↗
- https://github.com/py-pdf/pypdf/pull/3791 ↗
- https://github.com/py-pdf/pypdf/commit/507d7c9aa6ea83389b954b9c3c0c528fe5d5da70 ↗
- https://github.com/py-pdf/pypdf/releases/tag/6.12.0 ↗
- https://github.com/advisories/GHSA-248m-82v9-q6g6 ↗