# CVE-2025-62708: PYSEC-2026-1831 - pypdf can exhaust RAM via manipulated LZWDecode streams

Source: https://junglewise.ai/threats/cve-2025-62708-pypdf-can-exhaust-ram-via-manipulated-lzwdecode-streams  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-10-22  
License: CC BY 4.0 with a link back

CVE-2025-62708 · Severity: high · CVSS 7.5 · Published 2025-10-22

pypdf is a free and open-source pure-python PDF library. Prior to version 6.1.3, an attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing the content stream of a page using the LZWDecode filter. This has been fixed in pypdf version 6.1.3.

Technologies: [Pypdf Project Pypdf](https://junglewise.ai/threats/technologies/pypdf-project-pypdf), [pypdf (PyPI)](https://junglewise.ai/threats/technologies/pypdf). Vendors: [Pypdf Project](https://junglewise.ai/threats/vendors/pypdf-project), [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2025-62708 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-62708 being exploited in the wild.

**How severe is CVE-2025-62708?** High severity, with a CVSS score of 7.5, published 22 October 2025.

**Which products and versions are affected?** pypdf (PyPI) ECOSYSTEM:introduced=0,fixed=6.1.3.

**Is there a fix for CVE-2025-62708?** Yes. pypdf (PyPI): upgrade to 6.1.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2025-62708?** Check whether you run Pypdf Project Pypdf or pypdf (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- pypdf (PyPI): upgrade to 6.1.3 or later

  ```sh
  pip install "pypdf>=6.1.3"
  ```


## Affected products

- Pypdf Project Pypdf
- pypdf (PyPI) ECOSYSTEM:introduced=0,fixed=6.1.3

## Identifiers

- CVE-2025-62708
- GHSA-jfx9-29x2-rv3j
- PYSEC-2026-1831

## Related threats

- [pypdf memory exhaustion in cross-reference stream parsing](https://junglewise.ai/threats/cve-2026-119209-pypdf-is-a-free-and-open-source-pure-python-pdf-library-prior-to)
- [pypdf denial of service via forged encrypted PDF page count](https://junglewise.ai/threats/cve-2026-119208-pypdf-is-a-free-and-open-source-pure-python-pdf-library-prior-to)
- [pypdf excessive memory consumption in strict mode PDF parsing](https://junglewise.ai/threats/cve-2026-119207-pypdf-is-a-free-and-open-source-pure-python-pdf-library-prior-to)
- [pypdf denial of service via crafted page labels](https://junglewise.ai/threats/cve-2026-119206-pypdf-is-a-free-and-open-source-pure-python-pdf-library-prior-to)
- [pypdf infinite loop in DictionaryObject cloning](https://junglewise.ai/threats/cve-2026-119205-pypdf-is-a-free-and-open-source-pure-python-pdf-library-prior-to)