Vulnerability · Published Sep 14, 2026 · Assigned by GitHub_M

CVE-2026-55795Craft Commerce: Coupon Code Brute-Force via Rate Limit Bypass

Medium 6.9

In plain English

A medium-severity security flaw in commerce from craftcms. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)6.9Medium

Exploit odds (30 days)0.5%top 56.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Packagist	craftcms/commerce	5.6.5	GHSA-h5gm-x9wr-vhcm
Packagist	craftcms/commerce	4.11.2	GHSA-h5gm-x9wr-vhcm

Affected products (as reported)

Vendor	Product	Versions
craftcms	commerce	>= 4.0.0, < 4.11.2>= 5.0.0, < 5.6.5

Weakness: CWE-307 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

References

https://github.com/craftcms/commerce/security/advisories/GHSA-h5gm-x9wr-vhcm x_refsource_CONFIRM
https://github.com/craftcms/commerce/commit/a7d365cc33dc4c60c543defb3458bcdb5749bc13 x_refsource_MISC
https://github.com/craftcms/commerce/commit/df22c4f9c4ea7fb7857d833f755e49ea6f9f5bb5 x_refsource_MISC
https://github.com/craftcms/commerce/releases/tag/4.11.2 x_refsource_MISC
https://github.com/craftcms/commerce/releases/tag/5.6.5 x_refsource_MISC