CVE-2023-46250

pypdf possible Infinite Loop when PdfWriter(clone_from) is used with a PDF

Description

pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions 3.7.0 through 3.16.4 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 when the pypdf-user manipulates an incoming malicious PDF e.g. by merging it with another PDF or by adding annotations. The issue was fixed in version 3.17.0. As a workaround, apply the patch manually by modifying `pypdf/generic/_data_structures.py`.

Category

5.1
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.09%
Vendor Advisory github.com
Affected: py-pdf pypdf
Published at:
Updated at:

References

Link Tags
https://github.com/py-pdf/pypdf/security/advisories/GHSA-wjcc-cq79-p63f vendor advisory
https://github.com/py-pdf/pypdf/pull/2264 patch issue tracking
https://github.com/py-pdf/pypdf/commit/9b23ac3c9619492570011d551d521690de9a3e2d patch

Frequently Asked Questions

What is the severity of CVE-2023-46250?
CVE-2023-46250 has been scored as a medium severity vulnerability.
How to fix CVE-2023-46250?
To fix CVE-2023-46250, 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-2023-46250 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-46250 is being actively exploited. 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-2023-46250?
CVE-2023-46250 affects py-pdf pypdf.
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