CVE-2025-66019 (GCVE-0-2025-66019)
Vulnerability from cvelistv5
Published
2025-11-25 23:38
Modified
2026-01-20 18:33
Severity ?
6.6 (Medium) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Summary
pypdf is a free and open-source pure-python PDF library. Prior to version 6.4.0, an attacker who uses this vulnerability can craft a PDF which leads to a memory usage of up to 1 GB per stream. This requires parsing the content stream of a page using the LZWDecode filter. This issue has been patched in version 6.4.0.
References
Impacted products
Vendor Product Version
py-pdf pypdf Version: < 6.4.0
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