CVE-2026-115580High· 7.1▾ Twilightpypdf: Possible long runtimes for large xref table header limits
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 39.1 · likelihood 0 · exploitation 0
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An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires opening a file with large/wrong upper limits in the xref table.
This has been fixed in pypdf==6.21.2.
If you cannot upgrade yet, consider applying the changes from PR #4239.
pypdf < 6.21.2Upgrade to a patched release:
pypdf 6.21.2Connected by shared product, vendor, weakness, or advisory.
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