CVE-2026-71870

pypdf: Possible large memory usage for large /ToUnicode streams

Published: Aug 7, 2026Updated: Sep 9, 2026 Sources: CVE List NVDCWE-400

N/ACVSS

NVD MITRE

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a crafted PDF can cause large memory consumption when pypdf/_cmap.py function parse_bfrange parses unusually large source-code or destination-string tokens in a font /ToUnicode CMap during text extraction. This issue is fixed in 6.15.0.

No summary for this CVE yet.

Weaknesses

CWE-400

Affected Products

py-pdf

package-ecosystemaka pypdf2, pypdf

pypdfOn-prem

OSS Libraries / pypi

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Impact

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References

https://github.com/py-pdf/pypdf/commit/afba8080e19d29a3c256a742b340995e695b35aa

github.com

https://github.com/py-pdf/pypdf/pull/3944

github.com

https://github.com/py-pdf/pypdf/releases/tag/6.15.0

github.com

and 1 more references View all →

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