# CVE-2026-102994: pypdf denial of service in PDF object token parsing

Source: https://junglewise.ai/threats/cve-2026-102994-pypdf-is-a-free-and-open-source-pure-python-pdf-library-prior-to  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-30. Updated: 2026-09-30  
License: CC BY 4.0 with a link back

CVE-2026-102994 · Severity: high · CVSS 4 · Published 2026-09-30

pypdf is a Python library used to read and manipulate PDF files. A specially crafted PDF file can cause the library to scan very large amounts of data without stopping, consuming excessive CPU and memory resources. This can make applications using pypdf become unresponsive or crash, effectively disabling them until the operation completes or times out.

Technologies: [Py-Pdf Pypdf](https://junglewise.ai/threats/technologies/py-pdf-pypdf), [pypdf (PyPI)](https://junglewise.ai/threats/technologies/pypdf). Vendors: [Py-Pdf](https://junglewise.ai/threats/vendors/py-pdf), [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-102994 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-102994 being exploited in the wild.

**How severe is CVE-2026-102994?** High severity, with a CVSS score of 4, published 30 September 2026.

**Which products and versions are affected?** Py-Pdf Pypdf before 6.18.0; pypdf (PyPI) < 6.18.0, ECOSYSTEM:introduced=0,fixed=6.18.0.

**Is there a fix for CVE-2026-102994?** Yes. pypdf (PyPI): upgrade to 6.18.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-102994 attacked?** It is attacked with local access or over the network, in a software library.

**Am I affected by CVE-2026-102994?** Check whether you run Py-Pdf 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 6.18.0 or later

  ```sh
  pip install "pypdf>=6.18.0"
  ```


## Technical details

A malicious PDF containing indirect-object identifiers or generation-number tokens without whitespace delimiters can trigger excessive scanning in the read_until_whitespace function across pypdf/_reader.py and pypdf/generic/_base.py. The vulnerability is triggered during PDF parsing with no authentication or special user interaction required beyond opening the crafted PDF. The fix (version 6.18.0) implements a maximum length limit on these tokens to prevent unbounded scanning.

## Affected products

- py-pdf pypdf before 6.18.0

## Identifiers

- CVE-2026-102994
- GHSA-5jq2-8x83-x246
- PYSEC-2026-4153

## Timeline

- 2026-09-30: disclosed
- 2026-09-07: patched: Version 6.18.0 released with fix limiting indirect object token length

## References

- [https://github.com/py-pdf/pypdf/commit/82501d2993c6387833c4949d205caeb188f8bb9e](https://github.com/py-pdf/pypdf/commit/82501d2993c6387833c4949d205caeb188f8bb9e)
- [https://github.com/py-pdf/pypdf/pull/4055](https://github.com/py-pdf/pypdf/pull/4055)

## 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)