An attacker who uses this vulnerability can craft a PDF which leads to large memory consumption. This requires parsing the /ToUnicode entry of a font with unusually large values, for example during text extraction.
This has been fixed in pypdf==6.15.0.
If you cannot upgrade yet, consider applying the changes from PR #3944.
{
"github_reviewed": true,
"cwe_ids": [
"CWE-400"
],
"severity": "MODERATE",
"nvd_published_at": null,
"github_reviewed_at": "2026-08-07T19:29:09Z"
}