High severity · published Oct 23, 2026
CVE-2026-115585
pypdf: Possible long runtimes for repeated malformed cross-reference entries (Follow-up)
New
7.1
CVSS
0.4%
EPSS
No
On KEV
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.21.2, an incomplete remediation for repeated malformed cross-reference entries in GHSA-55h5-xmcq-c37v could still trigger a complete PDF stream reload during each recovery attempt even when a recovery cache was present, causing crafted cross-reference streams to produce long runtimes. This issue is fixed in version 6.21.2.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PY
pypdf · py-pdf
< 6.21.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-115585
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-115585
github.com
https://github.com/py-pdf/pypdf/commit/68a0e5046cc9e14a6c24a21a713f3c7fbde18b4b
github.com
https://github.com/py-pdf/pypdf/pull/4240
github.com
https://github.com/py-pdf/pypdf/releases/tag/6.21.2
github.com
https://github.com/py-pdf/pypdf/security/advisories/GHSA-jr96-gvgh-j3r4
More from pypdf
7.5
CVE-2026-103000
pypdf: Possible large memory usage when retrieving alphabetical page labels
7.5
CVE-2026-102999
pypdf: Possible long runtimes with large amount of embedded files
7.5
CVE-2026-102998
pypdf: Possible long runtimes when generating appearance streams
7.5
CVE-2026-102997
pypdf: Possible long runtimes for partially malformed FlateDecode streams (Follow-up)
7.5
CVE-2026-102996
pypdf: Possible large memory usage when parsing font data