CVE-2026-55795
CVE-2026-55795 — Craft Commerce: Coupon Code Brute-Force via Rate Limit Bypass
Craft Commerce is an ecommerce platform for Craft CMS. From 4.0.0 until 4.11.2 and 5.6.5, CartController in src/controllers/CartController.php activates its RateLimiter only when the number POST or GET parameter is supplied. An unauthenticated attacker can submit couponCode values to actionUpdateCart for the session-based cart while omitting number, preventing creation of the IP rate-limit identity and allowing unlimited automated coupon-code guessing and enumeration. This issue is fixed in versions 4.11.2 and 5.6.5.
Published Updated Sources: cvelistV5, GitHub_M
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
0%
chance of exploitation in 30 days
CVSS base
6.9
MEDIUM
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script all four kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component
Affected scope
The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.
Vendors (1)
Products (1)
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 6.9 | CVSS 4.0 | MEDIUM | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-307
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
- T1110.001Brute Force: Password Guessing
- T1078Valid Accounts
- T1110.003Brute Force: Password Spraying
Detection
Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.
- Search application, proxy, and WAF logs for requests touching /controllers/CartController.php.
References
5 on the record
- github.com/craftcms/commerce/security/advisories/GHSA-h5gm-x9wr-vhcm
x_refsource_CONFIRM
- github.com/craftcms/commerce/commit/a7d365cc33dc4c60c543defb3458bcdb5749bc13
x_refsource_MISC
- github.com/craftcms/commerce/commit/df22c4f9c4ea7fb7857d833f755e49ea6f9f5bb5
x_refsource_MISC
- github.com/craftcms/commerce/releases/tag/4.11.2
x_refsource_MISC
- github.com/craftcms/commerce/releases/tag/5.6.5
x_refsource_MISC
Elsewhere on this site
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.