CVE-2026-27025
MEDIUMpypdf < 6.7.1 - Denial of Service via Malicious /ToUnicode Font Entry
Title source: llmDescription
pypdf is a free and open-source pure-python PDF library. Prior to 6.7.1, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes and large memory consumption. This requires parsing the /ToUnicode entry of a font with unusually large values, for example during text extraction. This vulnerability is fixed in 6.7.1.
References (4)
Core 4
Core References
Vendor Advisory x_refsource_confirm
https://github.com/py-pdf/pypdf/security/advisories/GHSA-wgvp-vg3v-2xq3
Issue Tracking x_refsource_misc
https://github.com/py-pdf/pypdf/pull/3646
Patch x_refsource_misc
https://github.com/py-pdf/pypdf/commit/77d7b8d7cfbe8dd179858dfa42666f73fc6e57a2
Release Notes x_refsource_misc
https://github.com/py-pdf/pypdf/releases/tag/6.7.1
Scores
CVSS v3
5.5
EPSS
0.0017
EPSS Percentile
6.4%
Attack Vector
LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-834
Status
published
Products (2)
pypdf_project/pypdf
< 6.7.1
pypi/pypdf
0 - 6.7.1PyPI
Published
Feb 20, 2026
Tracked Since
Feb 21, 2026