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

Impact An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires reading the file. Patches This has been fixed in pypdf==6.7.2. Workarounds If users cannot upgrade yet, consider applying the changes from PR 3655...

CVE-2026-27628 pypdf has a possible infinite loop when loading circular /Prev entries in cross-reference streams

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...

SUSE CVE-2018-20481

XRef::getEntry in XRef.cc in Poppler 0.72.0 mishandles unallocated XRef entries, which allows remote attackers to cause a denial of service NULL pointer dereference via a crafted PDF document, when XRefEntry::setFlag in XRef.h is called from Parser::makeStream in Parser.cc...

DEBIAN-CVE-2018-20481

XRef::getEntry in XRef.cc in Poppler 0.72.0 mishandles unallocated XRef entries, which allows remote attackers to cause a denial of service NULL pointer dereference via a crafted PDF document, when XRefEntry::setFlag in XRef.h is called from Parser::makeStream in Parser.cc...