{"id":"CVE-2026-100678","title":"stoatchat before 0.15.5 fails to enforce account-level attempt limits on MFA login challenges, allowing attackers who know a password to guess TOTP codes with only IP-based rate limiting","summary":"stoatchat before 0.15.5 fails to enforce account-level attempt limits on MFA login challenges, allowing attackers who know a password to guess TOTP codes with only IP-based rate limiting. Attackers can reuse MFA challenge tickets across …","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N","cwe":["CWE-307"],"vendor":"stoatchat","product":"stoatchat","affected":["stoatchat < 0.15.5"],"published":"2026-09-26","updated":"2026-09-26","sourceUpdated":"2026-09-26T14:16:51.857","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-100678","references":[{"url":"https://github.com/stoatchat/stoatchat/security/advisories/GHSA-6877-g673-f5r8","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/stoatchat-before-0.15.5-mfa-brute-force-via-insufficient-rate-limiting","label":"disclosure@vulncheck.com"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-26T13:33:20.910Z","slug":"CVE-2026-100678","body":"## Overview\n\nstoatchat before 0.15.5 fails to enforce account-level attempt limits on MFA login challenges, allowing attackers who know a password to guess TOTP codes with only IP-based rate limiting. Attackers can reuse MFA challenge tickets across multiple failed attempts and distribute guesses across IP addresses to bypass rate limiting and gain account access.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}