CVE-2026-16365

Privilege escalation in the DOM: Workers component. This vulnerability was fixed in Firefox 153, Thunderbird 153, Firefox ESR 140.15, and Thunderbird 140.15.

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=2049149	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-68/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-71/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-84/
https://www.mozilla.org/security/advisories/mfsa2026-87/

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mozilla:firefox::::::::
	cpe:2.3:a:mozilla:thunderbird::::::::

History

No history.

Information

Published : 2026-07-21 13:17

Updated : 2026-09-01 22:17

NVD link : CVE-2026-16365

Mitre link : CVE-2026-16365

CVE.ORG link : CVE-2026-16365

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-269

Improper Privilege Management

CWE-284

Improper Access Control

{"id": "CVE-2026-16365", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-16365", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-07-24T03:55:28.271882Z"}}], "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": "Firefox", "versions": [{"status": "unaffected", "version": "140.15", "versionType": "rpm", "lessThanOrEqual": "140.*"}, {"status": "unaffected", "version": "153", "versionType": "rpm", "lessThanOrEqual": "*"}]}, {"vendor": "Mozilla", "product": "Thunderbird", "versions": [{"status": "unaffected", "version": "140.15", "versionType": "rpm", "lessThanOrEqual": "140.*"}, {"status": "unaffected", "version": "153", "versionType": "rpm", "lessThanOrEqual": "*"}]}]}], "published": "2026-07-21T13:17:05.037", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2049149", "tags": ["Permissions Required"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-68/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-71/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-84/", "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-87/", "source": "security@mozilla.org"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-269"}, {"lang": "en", "value": "CWE-284"}]}], "descriptions": [{"lang": "en", "value": "Privilege escalation in the DOM: Workers component. This vulnerability was fixed in Firefox 153, Thunderbird 153, Firefox ESR 140.15, and Thunderbird 140.15."}], "lastModified": "2026-09-01T22:17:10.530", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BD42740F-7A0F-4332-BFF3-46E0E8F37752", "versionEndExcluding": "153.0.0"}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "424BA860-1123-482C-9168-4A97E2EE0394", "versionEndExcluding": "153.0"}], "operator": "OR"}]}], "sourceIdentifier": "security@mozilla.org"}