CVE-2026-121553 (GCVE-0-2026-121553)
Vulnerability from cvelistv5
Published
2026-11-03 15:17
Modified
2026-11-07 03:09
Severity ?
6.3 (Medium) - CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
4.8 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L
CWE
  • CWE-338 - Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)
Summary
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.
References
Impacted products
Vendor Product Version
cotonti cotonti Version: 0   <
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