Low severity · published Aug 7, 2026
CVE-2026-71870
pypdf: Possible large memory usage for large /ToUnicode streams
3.3
CVSS
0.1%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 2% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PY
pypdf · py-pdf
< 6.15.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-71870
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-71870
Patch
https://github.com/py-pdf/pypdf/commit/afba8080e19d29a3c256a742b340995e695b35aa
Patch
https://github.com/py-pdf/pypdf/pull/3944
Release Notes
https://github.com/py-pdf/pypdf/releases/tag/6.15.0
Patch
https://github.com/py-pdf/pypdf/security/advisories/GHSA-fp3f-mc75-235c
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