Is there a public exploit for CVE-2026-121620?

No public exploit for CVE-2026-121620 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-121620?

CVE-2026-121620 scores CVSS 8.3 (v4.0), rated high.

What does CVE-2026-121620 affect?

CVE-2026-121620 affects CoopCycle coopcycle-web.

8.3 High

CoopCycle coopcycle-web 5.6.0 before 6.20.0 contains a missing authentication vulnerability that allows unauthenticated attackers to forge…

CVE-2026-121620

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.

Assessment

CVSS: 8.3 (v4.0)
Severity: High
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 4 November 2026
Last updated: 4 November 2026
Affected: CoopCycle · coopcycle-web
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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