watchOS 4 End of Life Date
watchOS 4 end-of-life date, support status, and CVE risk. Data from endoflife.date and official vendor documentation.
watchOS 4 was released on September 19, 2017 and support ended on September 17, 2018 — a supported lifespan of 1 year, in line with the 1 year median for watchOS releases. The last patch it will ever receive is 4.3.2, published July 9, 2018 — 2 months before support ended. It has been without security patches for 7 years and 11 months. 7 newer watchOS releases have shipped since.
What does watchOS 4 end of life mean?
When watchOS 4 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 watchOS 4 past its EOL date creates a permanently growing attack surface that standard security tooling will not surface.
Migrate to watchOS 26 or implement compensating controls — network segmentation, enhanced monitoring, restricted access — while migration is underway.