Medium severity5.3NVD Advisory· Published Aug 31, 2026· Updated Oct 5, 2026
CVE-2026-82398
CVE-2026-82398
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, an attacker can craft a PDF that causes long runtimes when the pypdf/_utils.py function read_until_whitespace reads a stream containing a long run of bytes without whitespace. The function repeatedly performs immutable bytes concatenation in a one-byte loop, causing quadratic processing cost for the long non-whitespace input. This issue is fixed in version 6.15.0.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
pypdfPyPI | < 6.15.0 | 6.15.0 |
Affected products
1Patches
Vulnerability mechanics
References
6- github.com/py-pdf/pypdf/commit/4959848e057e37c218dccad7465259210923faaanvdPatchWEB
- github.com/py-pdf/pypdf/pull/3947nvdPatchWEB
- github.com/py-pdf/pypdf/security/advisories/GHSA-fc8x-2rww-xw9mnvdPatchVendor AdvisoryWEB
- github.com/advisories/GHSA-fc8x-2rww-xw9mghsaADVISORY
- nvd.nist.gov/vuln/detail/CVE-2026-82398ghsaADVISORY
- github.com/py-pdf/pypdf/releases/tag/6.15.0nvdRelease NotesWEB
News mentions
0No linked articles in our index yet.