CVE-2023-36807

Public Exploit
Infinite Loop when reading malformed objects in pypdf

Description

pypdf is a pure-python PDF library capable of splitting, merging, cropping, and transforming the pages of PDF files. In version 2.10.5 an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. That is, for example, the case if the user extracted metadata from such a malformed PDF. Versions prior to 2.10.5 throw an error, but do not hang forever. This issue was fixed with https://github.com/py-pdf/pypdf/pull/1331 which has been included in release 2.10.6. Users are advised to upgrade. Users unable to upgrade should modify `PyPDF2/generic/_data_structures.py::read_object` to an an error throwing case. See GHSA-hm9v-vj3r-r55m for details.

Category

6.2
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.22%
Vendor Advisory github.com Vendor Advisory github.com
Affected: py-pdf pypdf
Published at:
Updated at:

References

Link Tags
https://github.com/py-pdf/pypdf/security/advisories/GHSA-hm9v-vj3r-r55m patch exploit vendor advisory mitigation
https://github.com/py-pdf/pypdf/issues/1329 vendor advisory issue tracking exploit
https://github.com/py-pdf/pypdf/pull/1331 patch

Frequently Asked Questions

What is the severity of CVE-2023-36807?
CVE-2023-36807 has been scored as a medium severity vulnerability.
How to fix CVE-2023-36807?
To fix CVE-2023-36807, 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-2023-36807 being actively exploited in the wild?
It is possible that CVE-2023-36807 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-2023-36807?
CVE-2023-36807 affects py-pdf pypdf.
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