Firefox 149 · Version Status

Firefox 149 End of Life Date

Firefox 149 end-of-life date, support status, and CVE risk. Data from endoflife.date and official vendor documentation.

Firefox 149 is past end of life. This version no longer receives security patches. 18 days past EOL — migrate to a supported version immediately.
EOL Date
Apr 21, 2026
18 days past EOL
Latest Release
149.0.2
Standard release
Release Date
Mar 24, 2026
Firefox 149 series
← Firefox 148 All Firefox versions Firefox 150 →
Recommended upgrade path
Firefox 150
Latest release: 150.0.2 · EOL: Supported
View full Firefox timeline →
All Firefox Versions
VersionLatestEOL DateStatus
78 LTS 78.15.0 Nov 2, 2021 EOL
91 LTS 91.13.0 Sep 20, 2022 EOL
102 LTS 102.15.1 Sep 26, 2023 EOL
103 103.0.2 Aug 23, 2022 EOL
104 104.0.2 Sep 20, 2022 EOL
105 105.0.3 Oct 18, 2022 EOL
106 106.0.5 Nov 15, 2022 EOL
107 107.0.1 Dec 13, 2022 EOL

What does Firefox 149 end of life mean?

When Firefox 149 reaches end of life, the maintainers stop issuing security patches for this version. CVEs discovered after the EOL date are publicly disclosed on the National Vulnerability Database with no patch available. Exploit code frequently appears on GitHub within days of disclosure.

The CVE blind spot: Most vulnerability scanners check for known CVEs but do not flag the ongoing accumulation of unpatched vulnerabilities in EOL software versions. Running Firefox 149 past its EOL date creates a permanently growing attack surface that standard security tooling will not surface.

Migrate to Firefox 150 or implement compensating controls — network segmentation, enhanced monitoring, restricted access — while migration is underway.

Frequently Asked Questions
When does Firefox 149 reach end of life?
Firefox 149 reached end of life on April 21, 2026. This version is no longer receiving security patches.
Is Firefox 149 still supported?
No. Firefox 149 reached end of life on April 21, 2026 and is no longer receiving security patches.
What should I upgrade to from Firefox 149?
The recommended upgrade from Firefox 149 is Firefox 150 — the latest actively supported version. Check the Firefox full timeline for all supported versions.
What are the security risks of running Firefox 149 past EOL?
When Firefox 149 reaches end of life, the maintainers stop issuing security patches. Any CVEs disclosed after the EOL date accumulate with no remediation path. Most vulnerability scanners do not flag this — it is the CVE blind spot. Organizations running EOL Firefox should migrate immediately or implement compensating controls.
Data from endoflife.date API · Generated at build time · How we source data →