CVE-2026-121620

MEDIUM 6.5

CoopCycle coopcycle-web 5.6.0 before 6.20.0 Missing Zelty Webhook Signature Verification

CVSS Score

6.5

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-345
Vendor	coopcycle
Product	coopcycle-web
Published	Nov 4, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:L

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

Low

Affected Versions

CoopCycle / coopcycle-web

5.6.0 < 6.20.0

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/coopcycle/coopcycle-web/commit/9b499950d433ca8ba894996d6b17f49885ca9485 github.com: https://github.com/coopcycle/coopcycle-web/releases/tag/v6.20.0 github.com: https://github.com/coopcycle/coopcycle-web/blob/v6.19.1/config/packages/security.yaml#L328-L330 github.com: https://github.com/coopcycle/coopcycle-web/blob/v6.19.1/src/Integration/Zelty/ZeltyCatalogProcessor.php#L51-L57 vulncheck.com: https://www.vulncheck.com/advisories/coopcycle-coopcycle-web-5.6.0-before-6.20.0-missing-zelty-webhook-signature-verification

Credits

Florian Kabashi