GHSA-63m5-974w-448v

Suggest an improvement
Source
https://github.com/advisories/GHSA-63m5-974w-448v
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-63m5-974w-448v/GHSA-63m5-974w-448v.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-63m5-974w-448v
Aliases
  • CVE-2026-23518
Published
2026-01-20T20:55:17Z
Modified
2026-01-20T21:12:13.532602Z
Severity
  • 9.3 (Critical) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
Fleet has a JWT signature bypass vulnerability in Azure AD MDM enrollment
Details

Impact

If Windows MDM is enabled, an attacker can enroll rogue devices by submitting a forged JWT containing arbitrary identity claims. Due to missing JWT signature verification, Fleet accepts these claims without validating that the token was issued by Azure AD, allowing enrollment under any Azure AD user identity.

Patches

  • 4.78.3
  • 4.77.1
  • 4.76.2
  • 4.75.2
  • 4.53.3

Workarounds

If an immediate upgrade is not possible, affected Fleet users should temporarily disable Windows MDM.

For more information

If you have any questions or comments about this advisory:

Email us at security@fleetdm.com Join #fleet in osquery Slack

Database specific
{
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-20T20:55:17Z",
    "severity": "CRITICAL",
    "nvd_published_at": null,
    "cwe_ids": [
        "CWE-347"
    ]
}
References

Affected packages

Go

github.com/fleetdm/fleet

Package

Name
github.com/fleetdm/fleet
View open source insights on deps.dev
Purl
pkg:golang/github.com/fleetdm/fleet

Affected ranges

Type
SEMVER
Events
Introduced
4.78.0
Fixed
4.78.3

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-63m5-974w-448v/GHSA-63m5-974w-448v.json"

github.com/fleetdm/fleet

Package

Name
github.com/fleetdm/fleet
View open source insights on deps.dev
Purl
pkg:golang/github.com/fleetdm/fleet

Affected ranges

Type
SEMVER
Events
Introduced
4.77.0
Fixed
4.77.1

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-63m5-974w-448v/GHSA-63m5-974w-448v.json"

github.com/fleetdm/fleet

Package

Name
github.com/fleetdm/fleet
View open source insights on deps.dev
Purl
pkg:golang/github.com/fleetdm/fleet

Affected ranges

Type
SEMVER
Events
Introduced
4.76.0
Fixed
4.76.2

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-63m5-974w-448v/GHSA-63m5-974w-448v.json"

github.com/fleetdm/fleet

Package

Name
github.com/fleetdm/fleet
View open source insights on deps.dev
Purl
pkg:golang/github.com/fleetdm/fleet

Affected ranges

Type
SEMVER
Events
Introduced
4.75.0
Fixed
4.75.2

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-63m5-974w-448v/GHSA-63m5-974w-448v.json"

github.com/fleetdm/fleet

Package

Name
github.com/fleetdm/fleet
View open source insights on deps.dev
Purl
pkg:golang/github.com/fleetdm/fleet

Affected ranges

Type
SEMVER
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
4.43.5-0.20260112202845-e225ef57912c

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/01/GHSA-63m5-974w-448v/GHSA-63m5-974w-448v.json"