# CVE-2023-36464: pypdf: pypdf is an open source, pure-python PDF library

CVE-2023-36464 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2023-36464, released June 27, 2023. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2023-36464
- Priority: Routine
- CVSS: 5.5 (medium)
- EPSS: 0.0035
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 27, 2023

## Description

pypdf is an open source, pure-python PDF library. In affected versions an attacker may craft a PDF which leads to an infinite loop if `__parse_content_stream` is executed. That is, for example, the case if the user extracted text from such a PDF. This issue was introduced in pull request #969 and resolved in pull request #1828. Users are advised to upgrade. Users unable to upgrade may modify the line `while peek not in (b"\r", b"\n")` in `pypdf/generic/_data_structures.py` to `while peek not in (b"\r", b"\n", b"")`.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | pypdf Debian 12.15 (bookworm) | 3.4.1-1+deb12u1 | [DEBIAN-CVE-2023-36464](https://patchblox.com/security/data/fix/linux/debian-cve-2023-36464.md) | Jun 27, 2023 |
| Linux | pypdf Debian 13.5 (trixie) | 3.17.4-1 | [DEBIAN-CVE-2023-36464](https://patchblox.com/security/data/fix/linux/debian-cve-2023-36464.md) | Jun 27, 2023 |
| Linux | pypdf Debian 14 | 3.17.4-1 | [DEBIAN-CVE-2023-36464](https://patchblox.com/security/data/fix/linux/debian-cve-2023-36464.md) | Jun 27, 2023 |
| Linux | pypdf2 Debian 12.15 (bookworm) | 2.12.1-3+deb12u1 | [DEBIAN-CVE-2023-36464](https://patchblox.com/security/data/fix/linux/debian-cve-2023-36464.md) | Jun 27, 2023 |

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Data as of 2026-11-09T01:18:40Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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