# CVE-2026-38076: Artifex jbig2dec integer overflow in jbig2_arith_iaid_ctx_new

Source: https://junglewise.ai/threats/cve-2026-38076-artifex-jbig2dec-integer-overflow-in-jbig2-arith-iaid-ctx-new  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-09. Updated: 2026-07-09  
License: CC BY 4.0 with a link back

CVE-2026-38076 · Severity: info · CVSS 5.5 · Published 2026-07-09

A vulnerability exists in the Artifex jbig2dec library, which is used for decoding JBIG2 images in software like MuPDF and Ghostscript. By providing a specially crafted image file, an attacker can cause the application to crash, leading to a denial of service. This could disrupt operations for users or automated systems processing document files.

Vendors: [Artifex Software](https://junglewise.ai/threats/vendors/artifex-software).

## Quick answers

**Is CVE-2026-38076 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-38076 being exploited in the wild.

**How severe is CVE-2026-38076?** Informational severity, with a CVSS score of 5.5, published 9 July 2026.

**Which products and versions are affected?** Artifex Software Jbig2dec Prior to commit cc37d09.

**Is there a fix for CVE-2026-38076?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-38076 attacked?** It is attacked with local access or over the network, in a software library.

**Am I affected by CVE-2026-38076?** Check whether you run Artifex Software Jbig2dec 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.

## Technical details

An integer overflow vulnerability exists in the jbig2_arith_iaid_ctx_new() function within jbig2_arith_iaid.c of the jbig2dec library. The flaw is rooted in insufficient validation of the SBSYMCODELEN parameter, which triggers a signed integer overflow during the decoding loop in jbig2_arith_iaid_decode(). An attacker can exploit this by providing a malicious JBIG2 image file to a linked application (such as MuPDF), resulting in out-of-bounds memory access and a subsequent application crash. The issue was addressed in commit cc37d09.

## Affected products

- Artifex Software jbig2dec Prior to commit cc37d09
- Artifex Software MuPDF

## Timeline

- 2026-07-06: other: Vulnerability details shared via GitHub Gist
- 2026-07-09: disclosed: CVE published to NVD

## References

- [http://artifex.com/](http://artifex.com/)
- [https://gist.github.com/dkjsone/c237b83ffa9ebd7028b5db7f410fcf78](https://gist.github.com/dkjsone/c237b83ffa9ebd7028b5db7f410fcf78)
- [https://github.com/ArtifexSoftware/jbig2dec](https://github.com/ArtifexSoftware/jbig2dec)