CVE-2026-27628

pypdf has a possible infinite loop when loading circular /Prev entries in cross-reference streams

At a glance

Severity: LOW 1.2
EPSS: EPSS 0.40 % · percentile 34 (2026-10-27)
State: PUBLISHED
Published: 2026-02-25
Updated: 2026-02-27
Assigner: GitHub_M
NVD status: Modified

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.7.2, an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires reading the file. This has been fixed in pypdf 6.7.2. As a workaround, one may apply the patch manually.

Scores

Version	Score	Vector	Scored by
CVSS 4.0	LOW 1.2	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U	GitHub_M
CVSS 4.0	LOW 1.2	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/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-2rw7-x74f-jg35 — pypdf has a possible infinite loop when loading circular /Prev entries in cross-reference streams
PYSEC-2026-3005 — pypdf has a possible infinite loop when loading circular /Prev entries in cross-reference streams

European references

ENISA EUVD · EUVD-2026-8601
GCVE · GCVE-0-2026-27628

CERT-FR advisories

CERTFR-2026-AVI-0627 — Multiples vulnérabilités dans les produits Splunk · cert.ssi.gouv.fr
CERTFR-2026-AVI-0424 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:* < 6.7.2

Affected products

Product	Versions
py-pdf · pypdf	affected < 6.7.2

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
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
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