CVE-2023-36810

Public Exploit
Quadratic runtime with malformed PDF missing xref marker in pypdf

Description

pypdf is a pure-python PDF library capable of splitting, merging, cropping, and transforming the pages of PDF files. An attacker who uses this vulnerability can craft a PDF which leads to unexpected long runtime. This quadratic runtime blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. This issue has been addressed in PR 808 and versions from 1.27.9 include this fix. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Category

6.2
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.13%
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-jrm6-h9cq-8gqw patch vendor advisory exploit
https://github.com/py-pdf/pypdf/issues/582 vendor advisory issue tracking exploit
https://github.com/py-pdf/pypdf/pull/808 patch
https://lists.debian.org/debian-lts-announce/2023/07/msg00019.html

Frequently Asked Questions

What is the severity of CVE-2023-36810?
CVE-2023-36810 has been scored as a medium severity vulnerability.
How to fix CVE-2023-36810?
To fix CVE-2023-36810, 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-2023-36810 being actively exploited in the wild?
It is possible that CVE-2023-36810 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-2023-36810?
CVE-2023-36810 affects py-pdf pypdf.
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