CVE-2026-42207 Magento LTS: Open Redirect via Unvalidated `uenc` Parameter in `stockAction()` - magento-lts
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-42207?
CVE-2026-42207 is a medium-severity vulnerability in OpenMage magento-lts, published on 15 May 2026.
Official 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 20.18.0, Mage_ProductAlert_AddController::stockAction() reads the uenc query parameter and passes it directly to $this->_redirectUrl($backUrl) without calling $this->_isUrlInternal(). When the supplied product_id does not match any catalog product, the server issues an unvalidated HTTP 302 redirect to whatever URL was provided as uenc. This vulnerability is fixed in 20.18.0.
Weakness: CWE-601
Which versions are affected by CVE-2026-42207?
2 open source packages ship an affected version, including openmage/magento-lts.
| Package | Affected | Fixed in |
|---|---|---|
openmage/magento-lts Packagist | All versions | 20.18.0 |
openmage/magento-lts Packagist | All versions | 20.18.0 |
How do I fix CVE-2026-42207?
Upgrade openmage/magento-lts to 20.18.0 or later.
Is CVE-2026-42207 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42207 exists.
Sources
Also known as GHSA-qpgq-5g92-j5q8.