7.1 High

pypdf: Possible long runtimes for repeated references to the same missing object

CVE-2026-115572

Impact An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires loading relevant parts of a file (like their pages) where the same, but non-existent indirect object is referenced multiple times. Patches This has been fixed in [pypdf==6.21.2](https://github.com/py-pdf/pypdf/releases/tag/6.21.2). Workarounds If you cannot upgrade yet, consider applying the changes from PR [#4240](https://github.com/py-pdf/pypdf/pull/4240).

Assessment

CVSS: 7.1 (v4.0)
Severity: High
EPSS: 0.00375% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 23 October 2026
Last updated: 23 October 2026
Affected: pip · pypdf
Weakness: CWE-400

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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