CVE-2026-100674 (GCVE-0-2026-100674)

Vulnerability from cvelistv5 – Published: 2026-09-26 13:23 – Updated: 2026-09-30 14:58
VLAI
Title
stoatchat before 0.15.5 Username Validation Bypass via Unicode Sanitization
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.
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-30 14:58 UTC
CWE
  • CWE-180 - Incorrect Behavior Order: Validate Before Canonicalize
Assigner
References
Impacted products
Vendor Product Version
stoatchat stoatchat Affected: 0 , < 0.15.5 (semver)
Unaffected: 0.15.5 (semver)
Create a notification for this product.
Date Public
2026-09-11 00:00
Show details on NVD website
To clipboard 

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