{"affected":[{"product":"Thunderbird","source":"CNA: mozilla","vendor":"Mozilla","versions":[{"lessThanOrEqual":"153.*","status":"unaffected","version":"153.6","versionType":"rpm"},{"lessThanOrEqual":"*","status":"unaffected","version":"159","versionType":"rpm"}]}],"cveId":"CVE-2026-118177","cwes":["CWE-601"],"description":"When looking for calendars in a directory on a server, during account setup or when adding a new network calendar, Thunderbird accepted calendar locations pointing to other servers, local files or network shares. A malicious server, or a network attacker when the lookup used plain HTTP, could make Thunderbird subscribe to such a location. On Windows this could leak the user's NTLM credentials to an attacker-controlled host on every calendar refresh, and changes to the calendar could be written to the attacker's share or overwrite a local file. This vulnerability was fixed in Thunderbird 159 and Thunderbird 153.6.","epss":{"date":"2026-11-04","percentile":0.07577,"score":0.00179},"exploits":[],"kev":null,"metrics":[{"score":9.1,"severity":"critical","source":"ADP: CISA-ADP","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","version":"3.1"},{"score":9.1,"severity":"critical","source":"NVD: 134c704f-9b21-4f2e-91b3-4a467353bcc0","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","version":"3.1"}],"modifiedAt":1793812653960,"publishedAt":1793124991083,"references":[{"source":"CNA: mozilla","tags":[],"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=2080924"},{"source":"CNA: mozilla","tags":[],"url":"https://www.mozilla.org/security/advisories/mfsa2026-121/"},{"source":"CNA: mozilla","tags":[],"url":"https://www.mozilla.org/security/advisories/mfsa2026-122/"},{"source":"security@mozilla.org","tags":[],"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=2080924"},{"source":"security@mozilla.org","tags":[],"url":"https://www.mozilla.org/security/advisories/mfsa2026-121/"},{"source":"security@mozilla.org","tags":[],"url":"https://www.mozilla.org/security/advisories/mfsa2026-122/"}],"remediation":[],"revision":"3449be98ef9d352964189d24e7b6cafdfc1130ab767621e0d172c1acf7931a23","sources":[{"modifiedAt":1793810801853,"name":"CNA: mozilla","retrievedAt":1793812179216,"url":"https://www.cve.org/CVERecord?id=CVE-2026-118177"},{"modifiedAt":1793812653960,"name":"NVD","retrievedAt":1793816560827,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-118177"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1793812191080,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-118177"}],"ssvc":{"assessedAt":1793810759914,"automatable":"yes","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"Calendar discovery accepted local file and remote network share locations","updatedAt":1793816560827}