# CVE-2026-120431: Netpbm heap-based buffer overflow in sgitopnm readChannels

Source: https://junglewise.ai/threats/cve-2026-120431-netpbm-before-10-86-51-11-x-before-11-02-29-and-11-03-before-11  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-02. Updated: 2026-11-02  
License: CC BY 4.0 with a link back

CVE-2026-120431 · Severity: high · CVSS 7.8 · Published 2026-11-02

Netpbm is a suite of graphics conversion tools widely used for batch image processing. A heap-based buffer overflow in sgitopnm, which converts SGI image files to other formats, can be triggered by supplying a malicious SGI file with crafted RLE compression data. An attacker can crash the application or potentially execute arbitrary code.

Technologies: [Netpbm](https://junglewise.ai/threats/technologies/netpbm). Vendors: [Netpbm](https://junglewise.ai/threats/vendors/netpbm).

## Quick answers

**Is CVE-2026-120431 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-120431 being exploited in the wild.

**How severe is CVE-2026-120431?** High severity, with a CVSS score of 7.8, published 2 November 2026.

**Which products and versions are affected?** Netpbm before 10.86.51, 11.x before 11.02.29, 11.03 before 11.15.07.

**Is there a fix for CVE-2026-120431?** Yes: fixed in Netpbm 10.86.51, 11.02.29, 11.15.07. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-120431 attacked?** It is attacked with local access or over the network, in a software library.

**Am I affected by CVE-2026-120431?** Check whether you run Netpbm 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

- Fixed in Netpbm 10.86.51, 11.02.29, 11.15.07

## Technical details

The readChannels() function in sgitopnm fails to properly validate the offset table length when processing RLE-compressed SGI images, allowing an attacker to write controlled data past the heap buffer boundary. The vulnerability is triggered by network or local supply of a crafted SGI file; no authentication or user interaction beyond opening the file is required. Successful exploitation leads to denial of service or arbitrary code execution with the privileges of the user running sgitopnm.

## Affected products

- Netpbm Netpbm before 10.86.51, 11.x before 11.02.29, 11.03 before 11.15.07

## Timeline

- 2026-11-02: disclosed

## References

- [https://sourceforge.net/p/netpbm/code/5317/](https://sourceforge.net/p/netpbm/code/5317/)
- [https://svn.code.sf.net/p/netpbm/code/!svn/bc/5316/trunk/converter/other/sgitopnm.c](https://svn.code.sf.net/p/netpbm/code/!svn/bc/5316/trunk/converter/other/sgitopnm.c)

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