SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-24688

An attacker who uses an infinite loop vulnerability that is present in versions prior to 6.6.2 can craft a PDF which leads to an infinite loop.

MEDIUM 5.1EPSS 0.45%

Does this matter?

Lower severity and a low EPSS score (0.45%). Track it; it rarely justifies an emergency change on its own.

Description

pypdf is a free and open-source pure-python PDF library. An attacker who uses an infinite loop vulnerability that is present in versions prior to 6.6.2 can craft a PDF which leads to an infinite loop. This requires accessing the outlines/bookmarks. This has been fixed in pypdf 6.6.2. If projects cannot upgrade yet, consider applying the changes from PR #3610 manually.

CVSS 4.0
5.1 MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.45% probability · 38th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-835
Affected
pypdf project/pypdf
Source
security-advisories@github.com
EPSS trend
0%3%5%26 October 2026: 0.45%26 October 202626 October 2026

EPSS 0.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.