Answer in brief
CVE-2026-121553 records a Medium severity (CVSS 6.3) vulnerability in Cotonti through 1.0.0 Predictable Validation Tokens via md5(microtime()). The current sources do not mark it as known exploited. The current feed maps cotonti/cotonti (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 6.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps cotonti/cotonti (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| cotonti/cotontigeneric | >=0 <=1.0.0 | Not reported |
Published upstream
Nov 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 3, 2026
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.
Quoted source text, attributed separately from HOL analysis.