Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
🐹 Go
Not in CISA KEV

GHSA-4r5r-ccr6-q6f6 fleet

Fix: fleetdm/fleet@5c030e3

GHSA-4r5r-ccr6-q6f6 is a CWE-862 vulnerability in github.com/fleetdm/fleet. A fix is available for github.com/fleetdm/fleet — see the affected versions and patch details below.

Fleet has an Access Control vulnerability in debug/pprof endpoints

Also known asCVE-2026-23517GO-2026-4334
Published
Jan 20, 2026
Updated
Feb 28, 2026
Affected
5 pkgs
Patched
5 / 5
Exploits
None indexed
Exploitation data as of Sep 18, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

  • A successful exploit gives an attacker total control of the affected component, not partial access.
  • CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-4r5r-ccr6-q6f6.

EPSS Exploitation Probability

via FIRST.org ↗
0.3%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs21th percentile — riskier than 21% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

5 pkgs affected
🐹github.com/fleetdm/fleet🐹github.com/fleetdm/fleet🐹github.com/fleetdm/fleet🐹github.com/fleetdm/fleet🐹github.com/fleetdm/fleet/v4

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

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

If you have any questions or comments about this advisory:

Email us at [email protected] Join #fleet in osquery Slack

Credits

We thank @secfox-ai for responsibly reporting this issue.

Affected Packages

5 total 5 fixed
EcosystemPackageVulnerable rangeFix
🐹Gogithub.com/fleetdm/fleet4.78.0&&< 4.78.34.78.3go get github.com/fleetdm/fleet@v4.78.3
🐹Gogithub.com/fleetdm/fleet4.77.0&&< 4.77.14.77.1go get github.com/fleetdm/fleet@v4.77.1
🐹Gogithub.com/fleetdm/fleet4.76.0&&< 4.76.24.76.2go get github.com/fleetdm/fleet@v4.76.2
🐹Gogithub.com/fleetdm/fleet4.75.0&&< 4.75.24.75.2go get github.com/fleetdm/fleet@v4.75.2
🐹Gogithub.com/fleetdm/fleet/v4all versions4.78.3-0.20260112221730-5c030e32a3a9go get github.com/fleetdm/fleet/v4@v4.78.3-0.20260112221730-5c030e32a3a9

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/fleetdm/fleet, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update github.com/fleetdm/fleet to 4.78.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4r5r-ccr6-q6f6 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-4r5r-ccr6-q6f6 can be triaged on real exposure rather than presence alone.

Tailored to GHSA-4r5r-ccr6-q6f6. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### 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 operatio
O3 Security · Impact-Aware SCA

Is GHSA-4r5r-ccr6-q6f6 in your dependencies?

O3 Security finds GHSA-4r5r-ccr6-q6f6 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

GHSA-4r5r-ccr6-q6f6: fleet DoS | O3 Security