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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
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.
- Record
CVE-2026-55795- CVSS 4.0
- 6.9 Medium
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 - Weakness
- CWE-307
- Updated
- 2026-11-02
EUVDEUVD-2026-77587
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.
- Record
EUVD-2026-77587- CVSS 4.0
- 6.9 Medium
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-h5gm-x9wr-vhcm
Craft Commerce: Coupon Code Brute-Force via Rate Limit Bypass
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.
- Record
GHSA-h5gm-x9wr-vhcm- CVSS 4.0
- 6.9 Medium
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 - Weakness
- CWE-307
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-55795- CVSS 4.0
- 6.9 Medium
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-307
- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2026-55795- CVSS 4.0
- 6.9 Medium
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 - Weakness
- CWE-307
- Updated
- 2026-11-02
OSVGHSA-h5gm-x9wr-vhcm
Craft Commerce: Coupon Code Brute-Force via Rate Limit Bypass
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.
- Record
GHSA-h5gm-x9wr-vhcm- CVSS 4.0
- 6.9 Medium
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 - Weakness
- CWE-307
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
craftcms/commercePackagist |
5.0.0 to 5.6.4 | 5.6.5 |
craftcms/commercePackagist |
4.0.0 to 4.11.1 | 4.11.2 |
craftcms/commercePackagist |
5.0.0 up to 5.6.5, plus listed versions 5.0.15.0.105.0.10.15.0.115.0.11.1 Show 45 moreShow less5.0.125.0.12.15.0.12.25.0.135.0.145.0.155.0.165.0.16.15.0.16.25.0.175.0.185.0.195.0.25.0.35.0.45.0.55.0.65.0.75.0.85.0.95.1.05.1.0-beta.15.1.0-beta.25.1.0-beta.35.1.0.15.1.15.1.25.1.35.1.45.2.05.2.15.2.105.2.115.2.125.2.12.15.2.25.2.2.15.2.35.2.45.2.55.2.65.2.75.2.85.2.95.2.9.1 |
5.6.5 |
craftcms/commercePackagist |
4.0.0 up to 4.11.2, plus listed versions 4.0.14.0.24.0.34.0.44.1.0 Show 45 moreShow less4.1.14.1.24.1.34.10.04.10.14.10.24.11.04.11.0.14.11.14.2.04.2.14.2.104.2.114.2.24.2.34.2.44.2.54.2.5.14.2.64.2.74.2.84.2.94.3.04.3.14.3.24.3.34.4.04.4.14.4.1.14.5.04.5.14.5.1.14.5.24.5.34.5.44.6.04.6.14.6.104.6.114.6.124.6.134.6.144.6.24.6.3.14.6.4 |
4.11.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-55795 is a medium vulnerability (CVSS 6.9) in Craftcms Commerce, published June 19, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.51%, the 43rd percentile. Fixed in craftcms/commerce 5.6.5.
References
github.com/craftcms/commerce/security/advisories/GHSA-h5gm-x9wr-vhcm
nvd.nist.gov/vuln/detail/CVE-2026-55795
Left out here: 66 versions. The JSON record has them.