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

Severity: high (CVSS 8.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-04-20 · updated 2026-10-26
Weakness: CWE-502

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.

Affected products

OpenMage magento-lts: before 20.17.0 — fixed in 20.17.0

How to fix

Upgrade to a fixed version: OpenMage magento-lts 20.17.0. Check the vendor advisory for mitigations.

References

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