CVE-2026-22690 is a medium severity vulnerability with a CVSS score of 5.3. No known exploits currently, and patches are available.
Very low probability of exploitation
EPSS predicts the probability of exploitation in the next 30 days based on real-world threat data, complementing CVSS severity scores with actual risk assessment.
An attacker who exploits this vulnerability can craft a PDF which leads to possibly long runtimes for actually invalid files. This can be achieved by omitting the /Root entry in the trailer, while using a rather large /Size value. Only the non-strict reading mode is affected.
This has been fixed in pypdf==6.6.0.
from pypdf import PdfReader, PdfWriter
# Instead of
reader = PdfReader("file.pdf")
# use the strict mode:
reader = PdfReader("file.pdf", strict=True)
# Instead of
writer = PdfWriter(clone_from="file.pdf")
# use an explicit strict reader:
writer = PdfWriter(clone_from=PdfReader("file.pdf", strict=True))
This issue has been fixed in #3594.
| Vendor | Product |
|---|---|
| Pypdf Project | Pypdf |
Please cite this page when referencing data from Strobes VI. Proper attribution helps support our vulnerability intelligence research.