CVE-2023-36810: py-pdf pypdf Inefficient Algorithmic Complexity

Vulnerability summary

CVE-2023-36810 is a medium (CVSS 6.5) Inefficient Algorithmic Complexity vulnerability in py-pdf pypdf. EPSS estimates a 0.63% chance of exploitation in the next 30 days, higher than 49.2% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 30-06-2023
   PublishedVulnerability first disclosed.
2. 13-02-2025
   Last modifiedVulnerability information updated.

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.

• CWE-407Inefficient Algorithmic ComplexityAn algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.