CVE-2026-23517: Fleet has an Access Control vulnerability in debug/pprof endpoints
Summary
A broken access control issue in Fleet allowed authenticated users to access debug and profiling endpoints regardless of role. As a result, low-privilege users could view internal server diagnostics and trigger resource-intensive profiling operations.
Impact
Fleet’s debug/pprof endpoints are accessible to any authenticated user regardless of role, including the lowest-privilege “Observer” role. This allows low-privilege users to access sensitive server internals, including runtime profiling data and in-memory application state, and to trigger CPU-intensive profiling operations that could lead to denial of service.
Patches
- 4.78.3 - 4.77.1 - 4.76.2 - 4.75.2 - 4.53.3
Workarounds
If an immediate upgrade is not possible, users should put the debug/pprof endpoints behind an IP allowlist.
For more information
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Credits
We thank @secfox-ai for responsibly reporting this issue.
Other sources
Fleet is open source device management software. A broken access control issue in versions prior to 4.78.3, 4.77.1, 4.76.2, 4.75.2, and 4.53.3 allowed authenticated users to access debug and profiling endpoints regardless of role. As a result, low-privilege users could view internal server diagnostics and trigger resource-intensive profiling operations. Fleet’s debug/pprof endpoints are accessible to any authenticated user regardless of role, including the lowest-privilege “Observer” role. This allows low-privilege users to access sensitive server internals, including runtime profiling data and in-memory application state, and to trigger CPU-intensive profiling operations that could lead to denial of service. Versions 4.78.3, 4.77.1, 4.76.2, 4.75.2, and 4.53.3 fix the issue. If an immediate upgrade is not possible, users should put the debug/pprof endpoints behind an IP allowlist as a workaround.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2026-23517?
CVE-2026-23517 is classified as a critical access control vulnerability affecting Fleet.
How do I fix CVE-2026-23517?
To resolve CVE-2026-23517, upgrade to Fleet version 4.78.3 or later.
Which versions of Fleet are affected by CVE-2026-23517?
CVE-2026-23517 affects Fleet versions 4.75.0 to 4.78.2.
What are the risks associated with CVE-2026-23517?
CVE-2026-23517 allows unauthorized access to debug and profiling information, potentially exposing sensitive server diagnostics.
Who is impacted by CVE-2026-23517?
Authenticated users with low privileges in Fleet can be impacted by CVE-2026-23517.