Resource exhaustion in Py-Pdf Pypdf

CVE-2026-102994

pypdf is a free and open-source pure-python PDF library. Prior to 6.18.0, a crafted PDF containing indirect-object identifiers or generation-number tokens that continue for a long time without whitespace can cause pypdf/_reader.py and pypdf/generic/_base.py to scan excessive input through read_until_whitespace, resulting in long runtimes and application unavailability. This issue is fixed in version 6.18.0.

Vulnerability class: DoS (Denial of Service)

Published · last modified .

EPSS exploit prediction

EPSS: 0.005 (42.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

The 30-day trend appears once there are two daily scores.

Affected products

Weakness classification (CWE)

References