CVE-2026-25523 — openmage/magento-lts
MEDIUMCVE-2026-25523 is a medium-severity (CVSS 5.3) Information Exposure vulnerability in openmage/magento-lts. A fix is available for openmage/magento-lts — see the affected versions and patch details below.
Magento's X-Original-Url header can expose admin url
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-25523.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-25523 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
openmage/magento-ltsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Impact
The admin url can be discovered without prior knowledge of it's location by exploiting the X-Original-Url header on some configurations.
Patches
The bug comes from the Zend library and is patche by unsetting the header in the bootstrap process.
Workarounds
Unset the X-Original-Url header in the web server configuration.
References
The activation of these headers is coming from the Zend_Controller module. It appears this has been known to some degree since 2016 - https://peterocallaghan.co.uk/2016/12/magento-poisoning-cache/ (dead link now..)
Credit
Anees Hyder ( @anees0xdev ) via HackerOne https://hackerone.com/anees0x_dev/hacktivity
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | openmage/magento-lts | all versions | 20.16.1composer require openmage/magento-lts:^20.16.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for openmage/magento-lts, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update openmage/magento-lts to 20.16.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-25523 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-25523 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-25523. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-25523 in your dependencies?
O3 Security finds CVE-2026-25523 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.