---
id: "CVE-2026-120434"
kind: "vulnerability"
aliases: ["CVE-2026-120434"]
title: "Netpbm: crafted PICT file overflows stack in picttoppm converter"
severity: "high"
cvss: 8.5
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["image-processing", "linux", "netpbm", "package"]
not_affected_if: ["no-untrusted-pict-input", "picttoppm-unused"]
published_at: "2026-11-02T15:17:25+00:00"
first_seen_at: "2026-11-02T15:24:02+00:00"
updated_at: "2026-11-02T15:25:57+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-120434", "first_seen_at": "2026-11-02T15:24:02+00:00"}]
---

# Netpbm: crafted PICT file overflows stack in picttoppm converter

Netpbm's picttoppm converter has a stack buffer overflow in its polygon handling, triggered when a PICT image has polygon edges producing more than 5000 points. An attacker who supplies a crafted PICT file can crash the converter or potentially run code.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed Netpbm version with `pnmcat --version` or your package manager, and compare it against the fixed ranges below.
- Find whether `picttoppm` is installed and used on untrusted PICT files, for example `which picttoppm`.

## Fix

- Netpbm `10.86.51` or later for the 10.x line
- Netpbm `11.02.30` or later for the 11.02.x line
- Netpbm `11.15.08` or later for the 11.03 line

## Timeline

- 2026-11-02T15:24:02+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-120434

## Documents

- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/netpbm-before-10.86.51-11.02.30-and-11.15.08-picttoppm-stack-overflow-via-scanpoly

## From the sources

Netpbm before 10.86.51, 11.x before 11.02.30, and 11.03 before 11.15.08 contains a stack-based buffer overflow in picttoppm's scanPoly() function in converter/ppm/picttoppm.c. Attackers can supply a crafted PICT file whose polygon edges produce more than 5000 points, overflowing the coord stack array to crash the converter or potentially execute code.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_