Summary
Fleet: Authorization Bypass in certificate template batch deletion for team administrators
A broken authorization check in Fleet’s certificate template deletion API could allow a team administrator to delete certificate templates belonging to other teams within the same Fleet instance.
Workarounds
If an immediate upgrade is not possible, administrators should restrict access to certificate template management to trusted users and avoid delegating team administrator permissions where not strictly required.
For more information
If there are any questions or comments about this advisory:
Email Fleet at [email protected]
Join #fleet in osquery Slack
Credits
Fleet thanks @secfox-ai for responsibly reporting this issue.
Impact
Fleet supports certificate templates that are scoped to individual teams. In affected versions, the batch deletion endpoint validated authorization using a user-supplied team identifier but did not verify that the certificate template IDs being deleted actually belonged to that team.
As a result, a team administrator could delete certificate templates associated with other teams, potentially disrupting certificate-based workflows such as device enrollment, Wi-Fi authentication, VPN access, or other certificate-dependent configurations for the affected teams.
This issue does not allow privilege escalation, access to sensitive data, or compromise of Fleet’s control plane. Impact is limited to integrity and availability of certificate templates across teams.
The application does not correctly enforce access controls, allowing a principal to access resources or operations beyond their granted permissions. Typical impact: unauthorized data access or execution of privileged operations.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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- v4.80.1
Frequently Asked Questions
- What is CVE-2026-25963? CVE-2026-25963 is a medium-severity incorrect authorization vulnerability in github.com/fleetdm/fleet/v4 (go), affecting versions < 4.80.1. It is fixed in 4.80.1. The application does not correctly enforce access controls, allowing a principal to access resources or operations beyond their granted permissions.
- Which versions of github.com/fleetdm/fleet/v4 are affected by CVE-2026-25963? github.com/fleetdm/fleet/v4 (go) versions < 4.80.1 is affected.
- Is there a fix for CVE-2026-25963? Yes. CVE-2026-25963 is fixed in 4.80.1. Upgrade to this version or later.
- Is CVE-2026-25963 exploitable, and should I be worried? Whether CVE-2026-25963 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-25963 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-25963? Upgrade
github.com/fleetdm/fleet/v4to 4.80.1 or later.