CVE-2026-118179

Clicking a news: or snews: link that referenced a message-ID made Thunderbird connect, without asking, to the host and port given in the link, even if it was not a configured news server. Line breaks in the message-ID were sent to the server unmodified, so a crafted link could send arbitrary commands to services reachable from the user's network. In addition, snews: links to such servers connected without TLS. This vulnerability was fixed in Thunderbird 159 and Thunderbird 153.6.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2077789
https://www.mozilla.org/security/advisories/mfsa2026-121/
https://www.mozilla.org/security/advisories/mfsa2026-122/

Configurations

No configuration.

History

04 Nov 2026, 17:17

Type	Values Removed	Values Added
CWE		CWE-20
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.8

27 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-27 19:17

Updated : 2026-11-04 17:17

NVD link : CVE-2026-118179

Mitre link : CVE-2026-118179

CVE.ORG link : CVE-2026-118179

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

{"id": "CVE-2026-118179", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-118179", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-11-04T16:43:19.420741Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.8, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.8}]}, "affected": [{"source": "security@mozilla.org", "affectedData": [{"vendor": "Mozilla", "product": "Thunderbird", "versions": [{"status": "unaffected", "version": "153.6", "versionType": "rpm", "lessThanOrEqual": "153.*"}, {"status": "unaffected", "version": "159", "versionType": "rpm", "lessThanOrEqual": "*"}]}]}], "published": "2026-10-27T19:17:29.590", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2077789", "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-121/", "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-122/", "source": "security@mozilla.org"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-20"}]}], "descriptions": [{"lang": "en", "value": "Clicking a news: or snews: link that referenced a message-ID made Thunderbird connect, without asking, to the host and port given in the link, even if it was not a configured news server. Line breaks in the message-ID were sent to the server unmodified, so a crafted link could send arbitrary commands to services reachable from the user's network. In addition, snews: links to such servers connected without TLS. This vulnerability was fixed in Thunderbird 159 and Thunderbird 153.6."}], "lastModified": "2026-11-04T17:17:34.280", "sourceIdentifier": "security@mozilla.org"}