CVE-2023-36464

Public Exploit
Infinite Loop when a comment isn't followed by a character in pypdf

Description

pypdf is an open source, pure-python PDF library. In affected versions an attacker may craft a PDF which leads to an infinite loop if `__parse_content_stream` is executed. That is, for example, the case if the user extracted text from such a PDF. This issue was introduced in pull request #969 and resolved in pull request #1828. Users are advised to upgrade. Users unable to upgrade may modify the line `while peek not in (b"\r", b"\n")` in `pypdf/generic/_data_structures.py` to `while peek not in (b"\r", b"\n", b"")`.

Category

6.2
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.02%
Affected: py-pdf pypdf
Published at:
Updated at:

References

Link Tags
https://github.com/py-pdf/pypdf/security/advisories/GHSA-4vvm-4w3v-6mr8 patch exploit
https://github.com/py-pdf/pypdf/pull/1828 patch
https://github.com/py-pdf/pypdf/pull/969 patch issue tracking

Frequently Asked Questions

What is the severity of CVE-2023-36464?
CVE-2023-36464 has been scored as a medium severity vulnerability.
How to fix CVE-2023-36464?
To fix CVE-2023-36464, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-36464 being actively exploited in the wild?
It is possible that CVE-2023-36464 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-36464?
CVE-2023-36464 affects py-pdf pypdf.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.