Google security teams have discovered 18 zero-day vulnerabilities in Samsung Exynos chips used in several top Android smartphones and wearables that may put those devices at risk.

Google's Project Zero head Tim Willis said in a blog post that four most severe of these vulnerabilities "allowed for Internet-to-baseband remote code execution".

Tests conducted by Project Zero confirmed that those four vulnerabilities allow an attacker to remotely compromise a phone at the baseband level with no user interaction, and require only that the attacker know the victim's phone number.

With limited additional research and development, "we believe that skilled attackers would be able to quickly create an operational exploit to compromise affected devices silently and remotely", said Google security researchers.

"Until security updates are available, users who wish to protect themselves from the baseband remote code execution vulnerabilities in Samsung's Exynos chipsets can turn off Wi-Fi calling and Voice-over-LTE (VoLTE) in their device settings," said Willis.

Turning off these settings will remove the exploitation risk of these vulnerabilities, he added.

The affected mobile devices are from Samsung, Vivo, Google (Pixel 6 and Pixel 7 series); any wearables that use the Exynos W920 chipset; and any vehicles that use the Exynos Auto T5123 chipset.

Google expects that patch timelines will vary per manufacturer, and affected Pixel devices have already received a fix.

"As always, we encourage end users to update their devices as soon as possible, to ensure that they are running the latest builds that fix both disclosed and undisclosed security vulnerabilities," said Google.