CVE-2026-16403
published 2026-07-21CVE-2026-16403: Spoofing issue in the Address Bar component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
PriorityP430medium6.5CVSS 3.1
AVNACLPRNUIRSUCNIHAN
EPSS
0.20%
9.9th percentile
Spoofing issue in the Address Bar component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 153 | Firefox 153 |
| mozilla | firefox | < 153.0.0 | 153.0.0 |
| mozilla | thunderbird | < Thunderbird 153 | Thunderbird 153 |
| mozilla | thunderbird | < 153.0 | 153.0 |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
vendor_redhat6.5MEDIUM
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Red Hat
firefox: thunderbird: Spoofing issue in the Address Bar component
vendor_redhat·2026-07-21·CVSS 6.5
CVE-2026-16403 [MEDIUM] firefox: thunderbird: Spoofing issue in the Address Bar component
firefox: thunderbird: Spoofing issue in the Address Bar component
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Spoofing issue in the Address Bar component
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: thunderbird (Red Hat Enterprise Linux 6) - Not affected
Package: firefox (Red H
Mozilla
Mozilla Foundation Security Advisory 2026-68: CVE-2026-16403
vendor_mozilla
CVE-2026-16403 Mozilla Foundation Security Advisory 2026-68: CVE-2026-16403
Mozilla Foundation Security Advisory 2026-68
CVE: CVE-2026-16403
Product: Firefox
Impact: high
Fixed in: Firefox 153
Mozilla
Mozilla Foundation Security Advisory 2026-71: CVE-2026-16403
vendor_mozilla
CVE-2026-16403 Mozilla Foundation Security Advisory 2026-71: CVE-2026-16403
Mozilla Foundation Security Advisory 2026-71
CVE: CVE-2026-16403
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 153
GHSA
Spoofing issue in the Address Bar component.
ghsa_unreviewed·2026-07-21
CVE-2026-16403 [MEDIUM] CWE-451 Spoofing issue in the Address Bar component.
Spoofing issue in the Address Bar component. This vulnerability was fixed in Firefox 153.
No detection rules found.
No public exploits indexed.
2026-07-21
Published