Bug 2442543 (CVE-2026-27628)

Summary:	CVE-2026-27628 pypdf: possible infinite loop when loading circular /Prev entries in cross-reference streams
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	anpicker, bbrownin, bdettelb, bparees, doconnor, hasun, jfula, jkoehler, jmitchel, jowilson, jwong, kshier, lphiri, nyancey, omaciel, ometelka, pbohmill, ptisnovs, syedriko, teagle, ttakamiy, xdharmai
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
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Doc Text:	A flaw was found in pypdf. Processing a specially crafted PDF document, specifically with circular /Prev references in the cross-reference (xref) chain, can cause an infinite loop and a high consumption of CPU, resulting in a denial of service.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2442636
Bug Blocks:

Description OSIDB Bzimport 2026-02-25 04:02:32 UTC

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.