Craft Commerce: Coupon Code Brute-Force via Rate Limit BypassGHSA-h5gm-x9wr-vhcm
Fix: craftcms/commerce@df22c4fGHSA-h5gm-x9wr-vhcm is a CWE-307 vulnerability in craftcms/commerce. A fix is available for craftcms/commerce — see the affected versions and patch details below.
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 GHSA-h5gm-x9wr-vhcm.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
craftcms/commerce🐘craftcms/commerceReal-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
Summary
The CartController defines a RateLimiter behavior that is only activated when the 'number' POST/GET parameter is explicitly provided.
Details
When an attacker submits coupon codes against the session-based cart (without passing a 'number' parameter), no rate limiting is applied. This allows unlimited attempts to guess coupon codes.
Vulnerable Code <img width="864" height="90" alt="resim" src="https://github.com/user-attachments/assets/a5197f10-f1fd-4331-93f9-9479d0ceebba" />
<img width="881" height="272" alt="resim" src="https://github.com/user-attachments/assets/d9db963f-5d1f-4b00-a4b4-5f2dfe2b71dd" /> <img width="861" height="271" alt="resim" src="https://github.com/user-attachments/assets/f7842493-3bc0-4e99-956c-7266bab15703" />PoC
Complete instructions, including specific configuration details, to reproduce the vulnerability.
<img width="909" height="171" alt="resim" src="https://github.com/user-attachments/assets/cfc8c994-5e0c-48de-b728-464029beba0e" />Impact
An attacker can enumerate all coupon codes through automated requests.
Remediation Apply rate limiting unconditionally on actionUpdateCart regardless of whether 'number' is present.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | craftcms/commerce | ≥ 5.0.0&&< 5.6.5 | 5.6.5composer require craftcms/commerce:^5.6.5 |
| 🐘Packagist | craftcms/commerce | ≥ 4.0.0&&< 4.11.2 | 4.11.2composer require craftcms/commerce:^4.11.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for craftcms/commerce, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update craftcms/commerce to 5.6.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h5gm-x9wr-vhcm 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.
Frequently Asked Questions
Is GHSA-h5gm-x9wr-vhcm in your dependencies?
Find it across Packagist, including transitive dependencies.