CVE-2026-8391

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2026-8391
Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.

5.3 /10

CVSS v3 : MEDIUM

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References
Link Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2038575 Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-45/ Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-47/
https://www.mozilla.org/security/advisories/mfsa2026-48/
https://www.mozilla.org/security/advisories/mfsa2026-51/
Configurations

Configuration 1 (hide)

cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
History

19 May 2026, 18:16

Type Values Removed Values Added
Summary (en) Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, and Firefox ESR 140.11. (en) Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.
References
  • () https://www.mozilla.org/security/advisories/mfsa2026-51/ -

19 May 2026, 14:16

Type Values Removed Values Added
References
  • () https://www.mozilla.org/security/advisories/mfsa2026-47/ -
  • () https://www.mozilla.org/security/advisories/mfsa2026-48/ -
Summary (en) Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3. (en) Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, and Firefox ESR 140.11.

13 May 2026, 17:22

Type Values Removed Values Added
References () https://bugzilla.mozilla.org/show_bug.cgi?id=2038575 - () https://bugzilla.mozilla.org/show_bug.cgi?id=2038575 - Permissions Required
References () https://www.mozilla.org/security/advisories/mfsa2026-45/ - () https://www.mozilla.org/security/advisories/mfsa2026-45/ - Vendor Advisory
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.3
First Time Mozilla
Mozilla firefox
CPE cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
CWE CWE-79
CWE-20
CWE-119

12 May 2026, 14:20

Type Values Removed Values Added
New CVE
Information

Published : 2026-05-12 14:17

Updated : 2026-05-19 18:16

NVD link : CVE-2026-8391

Mitre link : CVE-2026-8391

CVE.ORG link : CVE-2026-8391

JSON object : View

Products Affected

mozilla

  • firefox
CWE
CWE-20

Improper Input Validation

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-119

Improper Restriction of Operations within the Bounds of a Memory Buffer