Medium 4.8Published Aug 7, 2026

CVE-2026-71870pypdf: Possible large memory usage for large /ToUnicode streams

Updated under an hour ago (Oct 26, 2026, 4:23 PM ET)

Does this affect you?

It affects py-pdf pypdf and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for py-pdf pypdf

Exploited in the last 30 days

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: 4.8 MEDIUM (v4.0, CNA)CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Weakness (CWE): CWE-400
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Aug 10, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

py-pdf pypdf py_pdf:pypdf (from the name)	before 6.15.0	CNA record
pypdf_project pypdf pypdf_project:pypdf	before 6.15.0	NVD

References

References

https://github.com/py-pdf/pypdf/security/advisories/GHSA-fp3f-mc75-235c	x-refsource-confirm, patch, vendor-advisory
https://github.com/py-pdf/pypdf/pull/3944	x-refsource-misc, patch
https://github.com/py-pdf/pypdf/commit/afba8080e19d29a3c256a742b340995e695b35aa	x-refsource-misc, patch
https://github.com/py-pdf/pypdf/releases/tag/6.15.0	x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.