CVE-2026-121620
CoopCycle coopcycle-web 5.6.0 before 6.20.0 Missing Zelty Webhook Signature Verification
Description
CoopCycle coopcycle-web 5.6.0 before 6.20.0 contains a missing authentication vulnerability that allows unauthenticated attackers to forge Zelty webhook events because the x-zelty-hmac-sha256 HMAC signature is never verified. Attackers can POST forged dish, menu, option and order-status events to /api/zelty/webhook/* endpoints to toggle restaurant products and alter order preparation states.
INFO
Published Date :
Nov. 4, 2026, 1:17 p.m.
Last Modified :
Nov. 4, 2026, 1:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-121620
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update CoopCycle to version 6.20.0 or later.
- Verify webhook HMAC signature is always checked.
- Restrict access to webhook endpoints.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-121620.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-121620 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-121620
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-121620 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-121620 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Nov. 04, 2026
Action Type Old Value New Value Added Description CoopCycle coopcycle-web 5.6.0 before 6.20.0 contains a missing authentication vulnerability that allows unauthenticated attackers to forge Zelty webhook events because the x-zelty-hmac-sha256 HMAC signature is never verified. Attackers can POST forged dish, menu, option and order-status events to /api/zelty/webhook/* endpoints to toggle restaurant products and alter order preparation states. Added CVSS V4.0 AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:L/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 Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L Added CWE CWE-345 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/121xxx/CVE-2026-121620.json">CVE-2026-121620</a> Added Reference https://github.com/coopcycle/coopcycle-web/blob/v6.19.1/config/packages/security.yaml#L328-L330 Added Reference https://github.com/coopcycle/coopcycle-web/blob/v6.19.1/src/Integration/Zelty/ZeltyCatalogProcessor.php#L51-L57 Added Reference https://github.com/coopcycle/coopcycle-web/commit/9b499950d433ca8ba894996d6b17f49885ca9485 Added Reference https://github.com/coopcycle/coopcycle-web/releases/tag/v6.20.0 Added Reference https://www.vulncheck.com/advisories/coopcycle-coopcycle-web-5.6.0-before-6.20.0-missing-zelty-webhook-signature-verification