Vulnerability · Published Jun 30, 2023 · Assigned by GitHub_M
CVE-2023-36807Infinite Loop when reading malformed objects in pypdf
Medium 6.2
In plain English
A medium-severity infinite loop in pypdf from py-pdf. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 48% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | pypdf2 | 2.10.7-1 | DEBIAN-CVE-2023-36807 |
| PyPI | pypdf2 | 2.10.6 | GHSA-hm9v-vj3r-r55m |
| PyPI | pypdf2 | 2.10.6 | PYSEC-2026-1836 |
| Ubuntu:22.04:LTS | pypdf2 | 1.26.0-4ubuntu0.22.04.1 | UBUNTU-CVE-2023-36807 |
Affected products (as reported)
Weakness: CWE-835 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-hm9v-vj3r-r55m x_refsource_CONFIRM
- https://github.com/py-pdf/pypdf/issues/1329 x_refsource_MISC
- https://github.com/py-pdf/pypdf/pull/1331 x_refsource_MISC