Is CVE-2026-55795 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-55795 being exploited in the wild.

How severe is CVE-2026-55795?

Medium severity, with a CVSS score of 4, published 14 September 2026.

Which products and versions are affected?

craftcms/commerce (Packagist) ECOSYSTEM:introduced=5.0.0,fixed=5.6.5.

Is there a fix for CVE-2026-55795?

Yes. craftcms/commerce (Packagist): upgrade to 5.6.5 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-55795 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-55795?

Check whether you run craftcms/commerce (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-55795: Craft CMS Craft Commerce coupon brute-force via rate limit bypass

CVE-2026-55795 · Severity: medium · CVSS 4 · Published 2026-09-14

Craft Commerce, an e-commerce platform for Craft CMS, contains a vulnerability that allows attackers to bypass rate limits when guessing coupon codes. By omitting a specific parameter in their requests, attackers can make unlimited attempts to discover valid discount codes. This could lead to unauthorized use of high-value discounts and loss of revenue for store owners.

Technologies: craftcms/commerce (Packagist). Vendors: Packagist.

Quick answers

Is CVE-2026-55795 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-55795 being exploited in the wild.
How severe is CVE-2026-55795?: Medium severity, with a CVSS score of 4, published 14 September 2026.
Which products and versions are affected?: craftcms/commerce (Packagist) ECOSYSTEM:introduced=5.0.0,fixed=5.6.5.
Is there a fix for CVE-2026-55795?: Yes. craftcms/commerce (Packagist): upgrade to 5.6.5 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-55795 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-55795?: Check whether you run craftcms/commerce (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

craftcms/commerce (Packagist): upgrade to 5.6.5 or later
```
composer require craftcms/commerce:^5.6.5
```

Technical details

A rate limiting bypass exists in the Craft Commerce CartController's actionUpdateCart method. The RateLimiter behavior was conditionally activated only when the 'number' POST/GET parameter was explicitly provided. By submitting coupon codes against a session-based cart without this parameter, an attacker can bypass the intended rate limits. This allows for automated brute-force enumeration of valid coupon codes. The issue is fixed in versions 4.11.2 and 5.6.5 by applying rate limiting unconditionally.

Affected products

Craft CMS Commerce >= 4.0.0, <= 4.11.1
Craft CMS Commerce >= 5.0.0, <= 5.6.4

Identifiers

CVE-2026-55795
GHSA-h5gm-x9wr-vhcm

Timeline

2026-06-16: patched: Fix released in versions 4.11.2 and 5.6.5
2026-06-19: advisory: GitHub Advisory published

References

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