CVE-2026-120434
Description
A flaw was found in Netpbm. An attacker could exploit this vulnerability to achieve arbitrary code execution or cause a Denial of Service (DoS) by crashing the application. The flaw occurs in the picttoppm converter when processing a specially crafted PICT image containing an excessive number of polygon points, leading to a stack-based buffer overflow.
Statement
This vulnerability is rated as an Important severity flaw because an attacker who convinces a user or automated workflow to convert a malicious PICT image can achieve arbitrary code execution within the privileges of the running application. Netpbm utilities are local command-line tools rather than persistent network services, restricting exposure to environments where untrusted graphics are ingested or processed. While user interaction or automated ingestion is required, the potential for process takeover justifies the Important rating.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
--- CME Mitigation Guidance (2026-11-06) ---
Disclaimer: The following mitigation solutions are provided as a courtesy, pending the application of an official patch. This content was generated utilizing AI tools in conjunction with data from https://cmetaxonomy.org. Customers are advised to independently evaluate and test these temporary mitigations within their own infrastructure.
The highest-value action is to enforce stack canary protection on picttoppm to abort on scanPoly stack buffer corruption or prevent picttoppm from processing untrusted PICT images: upgrade to Netpbm 10.86.51, 11.02.30, or 11.15.08 (or the fixed Netpbm builds), which fix buffer overrun by properly handling very large polygons in picttoppm, closing crafted PICT file with excessive polygon points. Until patched, this is a concern on Linux hosts and automated ingestion workflows converting untrusted PICT files using picttoppm, so isolate or disable picttoppm in automated graphics conversion pipelines and prevent processing untrusted PICT images. As a compensating measure, enable address space layout randomization to impede reliable return-oriented programming execution following stack buffer overflow, build picttoppm as a position independent executable with full read-only relocations to harden binary layout, employ control flow integrity or shadow call stacks to validate return addresses and indirect branch targets, enforce SELinux to confine the picttoppm execution domain and limit post-exploitation privileges, deploy endpoint detection and response agents to monitor for crashes and abnormal process behavior from memory corruption, and use Falco or eBPF runtime monitoring to detect anomalous system calls and unexpected child process execution. These controls limit blast radius and contain exploitation, but they do not fix the underlying stack-based buffer overflow defect — apply the upstream patch to fully remediate.
Highest-impact CME: CME-301 SELinux (Enforcing Mode) (medium)
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.8 | N/A | 7.8 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | Required |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Memory; Execute Unauthorized Code or Commands
Write operations could cause memory corruption. In some cases, an adversary can modify control data such as return addresses in order to execute unexpected code.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
Attempting to access out-of-range, invalid, or unauthorized memory could cause the product to crash.
Other
Technical Impact: Unexpected State
Subsequent write operations can produce undefined or unexpected results.
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