Is there a public exploit for CVE-2026-121553?

No public exploit for CVE-2026-121553 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-2026-121553?

CVE-2026-121553 scores CVSS 6.3 (v4.0), rated medium.

What does CVE-2026-121553 affect?

CVE-2026-121553 affects Cotonti Cotonti.

6.3 Medium

Cotonti through 1.0.0 generates registration and email-change validation tokens with md5(microtime()), allowing attackers to bypass…

CVE-2026-121553

Cotonti through 1.0.0 generates registration and email-change validation tokens with md5(microtime()), allowing attackers to bypass email-ownership verification by predicting tokens. Attackers can derive the generation time from the HTTP Date header and compute candidate tokens offline. They then submit these tokens to the users.register.php validate handler to activate accounts or confirm email addresses they do not control.

Assessment

CVSS: 6.3 (v4.0)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 3 November 2026
Last updated: 3 November 2026
Affected: Cotonti · Cotonti
Assigner: VulnCheck

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

At the source

EUVD (ENISA)

References

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