CVE-2026-82398 (GCVE-0-2026-82398)

Vulnerability from cvelistv5 – Published: 2026-08-31 21:41 – Updated: 2026-09-01 14:57
VLAI
Title
pypdf: Inefficient handling of non-whitespace inputs in read_until_whitespace
Summary
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.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-01 14:18 UTC
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
Impacted products
Vendor Product Version
py-pdf pypdf Affected: < 6.15.0
Create a notification for this product.
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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