FKIE_CVE-2026-113866

Vulnerability from fkie_nvd - Published: 2026-10-20 20:17 - Updated: 2026-10-20 20:17
Severity
5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Summary
When setting up an account, Thunderbird's Exchange AutoDiscover lookup also queried the domain's AutoDiscover service over plain HTTP. Due to a bug, that unencrypted request included the credentials the user had entered, allowing a network attacker to obtain the user's password. This vulnerability was fixed in Thunderbird 158.0.1 and Thunderbird 153.5.1.
References
security@mozilla.orghttps://bugzilla.mozilla.org/show_bug.cgi?id=2080121
security@mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-114/
security@mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-115/
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Thunderbird",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "153.*",
              "status": "unaffected",
              "version": "153.5.1",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "158.0.1",
              "versionType": "rpm"
            }
          ]
        }
      ],
      "source": "security@mozilla.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "When setting up an account, Thunderbird\u0027s Exchange AutoDiscover lookup also queried the domain\u0027s AutoDiscover service over plain HTTP. Due to a bug, that unencrypted request included the credentials the user had entered, allowing a network attacker to obtain the user\u0027s password. This vulnerability was fixed in Thunderbird 158.0.1 and Thunderbird 153.5.1."
    }
  ],
  "id": "CVE-2026-113866",
  "lastModified": "2026-10-20T20:17:19.397",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.9,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-113866",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-10-20T19:35:34.601906Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-10-20T20:17:19.397",
  "references": [
    {
      "source": "security@mozilla.org",
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2080121"
    },
    {
      "source": "security@mozilla.org",
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-114/"
    },
    {
      "source": "security@mozilla.org",
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-115/"
    }
  ],
  "sourceIdentifier": "security@mozilla.org",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-523"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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