CVE-2025-27509: SAML authentication vulnerability due to improper SAML response validation

Severity: critical (CVSS 9.3 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-03-06 · updated 2026-06-17
Weakness: CWE-285

Description

fleetdm/fleet is an open source device management, built on osquery. In vulnerable versions of Fleet, an attacker could craft a specially-formed SAML response to forge authentication assertions, provision a new administrative user account if Just-In-Time (JIT) provisioning is enabled, or create new accounts tied to forged assertions if f MDM enrollment is enabled. This vulnerability is fixed in 4.64.2, 4.63.2, 4.62.4, and 4.58.1.

Affected products

fleetdm fleet: from 4.64.0, < 4.64.2; from 4.63.0, < 4.63.2; from 4.62.0, < 4.62.4; before 4.58.1

References

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