GHSA-4v8w-gg5j-ph37
CRITICALMantisBT vulnerable to authentication bypass for some passwords due to PHP type juggling
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.
Blast Radius
mantisbt/mantisbtReal-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
Due to an incorrect use of loose (==) instead of strict (===) comparison in the authentication code, PHP type juggling will cause interpretation of certain MD5 hashes as numbers, specifically those matching scientific notation.
Impact
On MantisBT instances configured to use the MD5 login method, user accounts having a password hash evaluating to zero (i.e. matching regex ^0+[Ee][0-9]+$) are vulnerable, allowing an attacker knowing the victim's username to login without knowledge of their actual password, using any other password having a hash evaluating to zero, for example comito5 (0e579603064547166083907005281618).
No password bruteforcing for individual users is needed, thus $g_max_failed_login_count does not protect against the attack.
Patches
Workarounds
Check the database for vulnerable accounts, and change those users' passwords, e.g. for MySQL:
SELECT username, email FROM mantis_user_table WHERE password REGEXP '^0+[Ee][0-9]+$'
References
Credits
Thanks to Harry Sintonen / Reversec for discovering and reporting the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | mantisbt/mantisbt | all versions | 2.27.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mantisbt/mantisbt. 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 mantisbt/mantisbt to 2.27.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4v8w-gg5j-ph37 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-4v8w-gg5j-ph37 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-4v8w-gg5j-ph37. 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-4v8w-gg5j-ph37 in your dependencies?
O3 detects GHSA-4v8w-gg5j-ph37 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.