An attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires cross-reference streams with /W [0 0 0] values and large /Size values.
This has been fixed in pypdf==6.12.0.
If developers are unable to upgrade their apps immediately, they should consider applying the changes from PR #3791.
{
"cwe_ids": [
"CWE-834"
],
"github_reviewed": true,
"github_reviewed_at": "2026-06-12T18:29:59Z",
"nvd_published_at": "2026-05-28T16:16:29Z",
"severity": "MODERATE"
}