CVE-2023-36464

Name: CVE-2023-36464
Creator: NVD / NIST
Published: 2023-06-27T22:15:11.79+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.34%

Last modified Jun 17, 2026

CVE-2023-36464 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. 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. EPSS estimates a 0.34% chance of exploitation in the next 30 days.

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"")`.

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

EPSS Probability

0.34%

26.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-835

Affected Software

Vendor	Product	Versions
Pypdf Project	Pypdf	< 3.9.0
Pypdf2 Project	Pypdf2	>= 2.2.0

References

https://github.com/py-pdf/pypdf/pull/1828Patch
https://github.com/py-pdf/pypdf/pull/969Issue Tracking, Patch
https://github.com/py-pdf/pypdf/security/advisories/GHSA-4vvm-4w3v-6mr8Exploit, Patch
https://github.com/py-pdf/pypdf/pull/1828Patch
https://github.com/py-pdf/pypdf/pull/969Issue Tracking, Patch
https://github.com/py-pdf/pypdf/security/advisories/GHSA-4vvm-4w3v-6mr8Exploit, Patch

Timeline

Published: Jun 27, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-36464?

How severe is CVE-2023-36464?

CVE-2023-36464 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.34% probability of exploitation in the next 30 days.

How do I fix CVE-2023-36464?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-36464?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST