GHSA-mj9p-v2r8-wf8w
MEDIUMGHSA-mj9p-v2r8-wf8w is a medium-severity (CVSS 4.4) Cross-site Scripting (XSS) vulnerability in simplesamlphp/simplesamlphp. O3 Security confirms whether GHSA-mj9p-v2r8-wf8w is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Cross-site scripting in SimpleSAMLphp
Real-World Exposure
simplesamlphp/simplesamlphpReal-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
Background
SimpleSAMLphp allows users to report errors and failures to the system administrators via a web form. This web form gathers some contextual information automatically, but it also allows the user to provide their email address for follow-ups and a free-text explanation of what happened. Once submitted, the report is sent as an email to the administrative email address configured in the software.
Description
The www/erroreport.php script allows error reports to be submitted and sent to the system administrator. Starting with SimpleSAMLphp 1.18.0, a new SimpleSAML\Utils\EMail class was introduced to handle sending emails, implemented as a wrapper of an external dependency.
This new wrapper allows us to use Twig templates in order to create the email sent with an error report. Since Twig provides automatic escaping of variables, manual escaping of the free-text field in www/errorreport.php was removed to avoid double escaping. However, for those not using the new user interface yet, an email template is hardcoded into the class itself in plain PHP. Since no escaping is provided in this template, it is then possible to inject HTML inside the template by manually crafting the contents of the free-text field.
Affected versions
SimpleSAMLphp versions 1.18.0 to 1.18.3, both inclusive.
Impact
An attacker may take advantage of this issue to manually craft a modified email sent via the error reporting mechanism, such as this email might trick a system administrator into performing an action, such as introducing their credentials into a phishing web site that resembles the original.
Remote execution of javascript code is considered unfeasible since email clients do not run javascript present in emails, although there might be email clients which don't follow this rule, making the attack surface grow.
Resolution
Upgrade the SimpleSAMLphp installation to version 1.18.4.
Credit
This vulnerability was discovered and reported by Frederic Vleminckx.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | simplesamlphp/simplesamlphp | ≥ 1.18.0&&< 1.18.4 | 1.18.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for simplesamlphp/simplesamlphp. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update simplesamlphp/simplesamlphp to 1.18.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-mj9p-v2r8-wf8w 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 pinpoints whether GHSA-mj9p-v2r8-wf8w is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-mj9p-v2r8-wf8w. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-mj9p-v2r8-wf8w in your dependencies?
O3 detects GHSA-mj9p-v2r8-wf8w across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.