CVE-2026-100674 (GCVE-0-2026-100674)
Vulnerability from cvelistv5
Published
2026-09-26 13:23
Modified
2026-09-30 14:58
Severity ?
5.3 (Medium) - CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
4.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
CWE
  • CWE-180 - Incorrect Behavior Order: Validate Before Canonicalize
Summary
stoatchat before 0.15.5 fails to revalidate usernames after Unicode sanitization, allowing attackers to create usernames with forbidden characters by submitting Unicode letters that transform into rejected characters. Attackers can bypass character allowlists and length limits to create reserved-name lookalikes, embed special characters, and exceed the 32-character storage limit.
References
Impacted products
Vendor Product Version
stoatchat stoatchat Version: 0   ≤
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