# CVE-2026-21304: Adobe InDesign Desktop heap-based buffer overflow

Source: https://junglewise.ai/threats/cve-2026-21304-adobe-indesign-desktop-heap-based-buffer-overflow  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-01-13. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-21304 · Severity: high · CVSS 7.8 · Published 2026-01-13

InDesign is a professional desktop publishing application used by designers and publishers to create layouts and print materials. A heap-based buffer overflow vulnerability could allow an attacker to execute arbitrary code on a user's computer if they trick the user into opening a malicious document. This could lead to complete compromise of the user's system, including data theft and malware installation.

Technologies: [Adobe InDesign Desktop](https://junglewise.ai/threats/technologies/indesign). Vendors: [Adobe](https://junglewise.ai/threats/vendors/adobe).

## Quick answers

**Is CVE-2026-21304 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-21304 being exploited in the wild.

**How severe is CVE-2026-21304?** High severity, with a CVSS score of 7.8, published 13 January 2026.

**Which products and versions are affected?** Adobe InDesign Desktop 21.0, 19.5.5 and earlier.

**Is there a fix for CVE-2026-21304?** 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-2026-21304 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-21304?** Check whether you run Adobe InDesign Desktop 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

InDesign Desktop versions 21.0, 19.5.5 and earlier contain a heap-based buffer overflow vulnerability in file parsing logic. The vulnerability is triggered when a user opens a specially crafted malicious file, causing a heap buffer to be overflowed. Exploitation requires user interaction (opening a malicious file) but no authentication. A successful exploit allows an attacker to execute arbitrary code in the context of the current user with the privileges of that user account.

## Affected products

- Adobe InDesign Desktop 21.0, 19.5.5 and earlier

## Timeline

- 2026-01-13: disclosed

## References

- [https://helpx.adobe.com/security/products/indesign/apsb26-02.html](https://helpx.adobe.com/security/products/indesign/apsb26-02.html)

## Related threats

- [Adobe InDesign Desktop NULL pointer dereference](https://junglewise.ai/threats/cve-2026-84396-indesign-desktop-is-affected-by-a-null-pointer-dereference)
- [Adobe InDesign Desktop null pointer dereference](https://junglewise.ai/threats/cve-2026-76192-indesign-desktop-is-affected-by-a-null-pointer-dereference)
- [Adobe InDesign heap overflow in file processing](https://junglewise.ai/threats/cve-2026-34699-adobe-indesign-heap-overflow-in-file-processing)
- [Adobe InDesign Desktop heap buffer overflow](https://junglewise.ai/threats/cve-2026-21358-adobe-indesign-desktop-heap-buffer-overflow)
- [Adobe InDesign Desktop heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-21357-adobe-indesign-desktop-heap-based-buffer-overflow)