CVE-2026-8960
published 2026-05-19CVE-2026-8960: Spoofing issue in WebExtensions. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
PriorityP339high7.5CVSS 3.1
AVNACLPRNUINSUCNIHAN
EPSS
0.38%
29.8th percentile
Spoofing issue in WebExtensions. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 151 | Firefox 151 |
| mozilla | firefox | < 151.0.0 | 151.0.0 |
| mozilla | thunderbird | < Thunderbird 151 | Thunderbird 151 |
| mozilla | thunderbird | < 151.0.0 | 151.0.0 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
vendor_redhat7.5HIGH
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Red Hat
firefox: thunderbird: Spoofing issue in WebExtensions
vendor_redhat·2026-05-19·CVSS 7.5
CVE-2026-8960 [HIGH] CWE-501 firefox: thunderbird: Spoofing issue in WebExtensions
firefox: thunderbird: Spoofing issue in WebExtensions
Spoofing issue in WebExtensions. This vulnerability was fixed in Firefox 151 and Thunderbird 151.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Spoofing issue in WebExtensions
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: firefox (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: thunderbird (Red Hat Enterprise Linux 10) - Not affected
Package: firefox (Red Hat Enterprise Linux 6) - Not affected
Package: thund
Mozilla
Mozilla Foundation Security Advisory 2026-46: CVE-2026-8960
vendor_mozilla·CVSS 7.5
CVE-2026-8960 [HIGH] Mozilla Foundation Security Advisory 2026-46: CVE-2026-8960
Mozilla Foundation Security Advisory 2026-46
CVE: CVE-2026-8960
Product: Firefox
Impact: high
Fixed in: Firefox 151
Mozilla
Mozilla Foundation Security Advisory 2026-50: CVE-2026-8960
vendor_mozilla·CVSS 7.5
CVE-2026-8960 [HIGH] Mozilla Foundation Security Advisory 2026-50: CVE-2026-8960
Mozilla Foundation Security Advisory 2026-50
CVE: CVE-2026-8960
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 151
GHSA
GHSA-57v8-q85x-pwx6: Spoofing issue in WebExtensions
ghsa_unreviewed·2026-05-19
CVE-2026-8960 [HIGH] CWE-290 GHSA-57v8-q85x-pwx6: Spoofing issue in WebExtensions
Spoofing issue in WebExtensions. This vulnerability was fixed in Firefox 151.
VulDB
Mozilla Firefox up to 150 WebExtensions
vuldb·2026-05-19·CVSS 7.5
CVE-2026-8960 [HIGH] Mozilla Firefox up to 150 WebExtensions
A vulnerability was found in Mozilla Firefox up to 150. It has been declared as problematic. The affected element is an unknown function of the component WebExtensions. Executing a manipulation can lead to an unknown weakness.
This vulnerability appears as CVE-2026-8960. The attack may be performed from remote. There is no available exploit.
It is recommended to upgrade the affected component.
No detection rules found.
No public exploits indexed.
2026-05-19
Published