stoatchat before 0.15.5 MFA Brute Force via Insufficient Rate Limiting

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-100678",
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "dateUpdated": "2026-09-26T13:23:40.935Z",
    "dateReserved": "2026-09-26T02:36:51.809Z",
    "datePublished": "2026-09-26T13:23:40.935Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck",
        "dateUpdated": "2026-09-26T13:23:40.935Z"
      },
      "datePublic": "2026-09-11T00:00:00.000Z",
      "title": "stoatchat before 0.15.5 MFA Brute Force via Insufficient Rate Limiting",
      "descriptions": [
        {
          "lang": "en",
          "value": "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 multiple failed attempts and distribute guesses across IP addresses to bypass rate limiting and gain account access."
        }
      ],
      "affected": [
        {
          "vendor": "stoatchat",
          "product": "stoatchat",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "0.15.5"
            },
            {
              "version": "0.15.5",
              "status": "unaffected",
              "versionType": "semver"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "Improper Restriction of Excessive Authentication Attempts",
              "cweId": "CWE-307",
              "type": "CWE"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://github.com/stoatchat/stoatchat/security/advisories/GHSA-6877-g673-f5r8",
          "name": "GitHub Security Advisory (GHSA-6877-g673-f5r8)",
          "tags": [
            "vendor-advisory"
          ]
        },
        {
          "url": "https://www.vulncheck.com/advisories/stoatchat-before-0.15.5-mfa-brute-force-via-insufficient-rate-limiting",
          "name": "VulnCheck Advisory: stoatchat before 0.15.5 MFA Brute Force via Insufficient Rate Limiting",
          "tags": [
            "third-party-advisory"
          ]
        }
      ],
      "metrics": [
        {
          "format": "CVSS"
        },
        {
          "format": "CVSS",
          "cvssV3_1": {
            "version": "3.1",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N",
            "attackVector": "NETWORK",
            "attackComplexity": "HIGH",
            "privilegesRequired": "NONE",
            "userInteraction": "NONE",
            "scope": "UNCHANGED",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "LOW",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM"
          }
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "QuentinRa",
          "type": "reporter"
        }
      ]
    }
  }
}