CVE-2026-12309

Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2038476	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-57/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-58/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-60/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-61/	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mozilla:firefox:::::esr:::*
	cpe:2.3:a:mozilla:firefox:::::-:::*
	cpe:2.3:a:mozilla:thunderbird:::::esr:::*
	cpe:2.3:a:mozilla:thunderbird:::::-:::*

History

No history.

Information

Published : 2026-06-16 13:16

Updated : 2026-06-18 19:16

NVD link : CVE-2026-12309

Mitre link : CVE-2026-12309

CVE.ORG link : CVE-2026-12309

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-119

Improper Restriction of Operations within the Bounds of a Memory Buffer

{"id": "CVE-2026-12309", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-12309", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-06-16T17:39:57.781816Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "LOW", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 2.5, "exploitabilityScore": 3.9}]}, "affected": [{"source": "security@mozilla.org", "affectedData": [{"vendor": "Mozilla", "product": "Firefox", "versions": [{"status": "unaffected", "version": "140.12", "versionType": "rpm", "lessThanOrEqual": "140.*"}, {"status": "unaffected", "version": "152", "versionType": "rpm", "lessThanOrEqual": "*"}]}, {"vendor": "Mozilla", "product": "Thunderbird", "versions": [{"status": "unaffected", "version": "140.12", "versionType": "rpm", "lessThanOrEqual": "140.*"}, {"status": "unaffected", "version": "152", "versionType": "rpm", "lessThanOrEqual": "*"}]}]}], "published": "2026-06-16T13:16:31.180", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2038476", "tags": ["Permissions Required"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-57/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-58/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-60/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-61/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-119"}]}], "descriptions": [{"lang": "en", "value": "Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12."}], "lastModified": "2026-06-18T19:16:21.220", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*", "vulnerable": true, "matchCriteriaId": "8FD731FB-146D-4A0A-83A3-63D926F4E653", "versionEndExcluding": "140.12.0"}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*", "vulnerable": true, "matchCriteriaId": "26C07C15-4B40-4068-A2F1-BE3E597D14B7", "versionEndExcluding": "152.0.0"}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*", "vulnerable": true, "matchCriteriaId": "767E6445-0CE7-46B5-A02B-EC06D37E45F8", "versionEndExcluding": "140.12.0"}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*", "vulnerable": true, "matchCriteriaId": "77D88ED0-AABD-4312-98B8-3D4B70226577", "versionEndExcluding": "152.0.0"}], "operator": "OR"}]}], "sourceIdentifier": "security@mozilla.org"}