CVE-2026-33699

pypdf: Possible infinite loop during recovery attempts in DictionaryObject.read_from_stream

At a glance

Severity: MEDIUM 4.6
EPSS: EPSS 0.47 % · percentile 41 (2026-10-27)
State: PUBLISHED
Published: 2026-03-26
Updated: 2026-03-27
Assigner: GitHub_M
NVD status: Analyzed

Description

pypdf is a free and open-source pure-python PDF library. Versions prior to 6.9.2 have a vulnerability in which an attacker can craft a PDF which leads to an infinite loop. This requires reading a file in non-strict mode. This has been fixed in pypdf 6.9.2. If users cannot upgrade yet, consider applying the changes from the patch manually.

Scores

Version	Score	Vector	Scored by
CVSS 4.0	MEDIUM 4.6	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U	GitHub_M
CVSS 4.0	MEDIUM 4.6	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X	NVD · security-advisories@github.com (Secondary)
CVSS 3.1	HIGH 7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	NVD · nvd@nist.gov (Primary)

Weaknesses (CWE)

CWE-835

Advisories

GHSA-87mj-5ggw-8qc3 — pypdf: Possible infinite loop during recovery attempts in DictionaryObject.read_from_stream
PYSEC-2026-3012 — pypdf: Possible infinite loop during recovery attempts in DictionaryObject.read_from_stream

European references

ENISA EUVD · EUVD-2026-16496
GCVE · GCVE-0-2026-33699

Affected configurations (NVD CPE)

cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:* < 6.9.2

Affected products

Product	Versions
py-pdf · pypdf	affected < 6.9.2

References

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD