CVE-2026-103264 Fleet before 4.87.0 Authentication Bypass via Device Identifiers

Critical 9.3 Published 1 Oct 2026 Updated 1 Oct 2026

Unauthenticated attackers can bypass authentication using non-secret device identifiers to read data and execute actions on iOS/iPadOS hosts.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-103264?

CVE-2026-103264 is a critical authentication bypass vulnerability in fleetdm fleet, published on 1 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Fleet versions before 4.87.0 contain an authentication bypass vulnerability in the device API that accepts hostnames and hardware serials as authentication tokens in addition to device UUIDs. Unauthenticated attackers who know or guess these non-secret identifiers can authenticate as iOS/iPadOS hosts to read device data and trigger device-scoped actions including software installation and MDM migration.

Weakness: CWE-287

Which versions are affected by CVE-2026-103264?

It affects 1 product.

Products include Fleetdm Fleet.

How do I fix CVE-2026-103264?

No fix has been published for CVE-2026-103264 yet. Limit exposure of the affected software until one is available.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2026-103264 being exploited?

There is no known exploitation of CVE-2026-103264 in the wild and no public exploit code.

Sources

Also known as GHSA-rmfg-c7hm-wv58, GHSA-vrc8-2wcx-327f.