CVEvulnerability
CVE-2020-26276
9.8 CRITICAL
Official page ↗
- Status
- Modified
- Published
- 2020-12-17
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 10.0 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
- CVSS 3.1 ([email protected])
- 9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CVSS 2.0 ([email protected])
- 6.8 MEDIUM — AV:N/AC:M/Au:N/C:P/I:P/A:P
- Weaknesses
- CWE-290
Description
Fleet is an open source osquery manager. In Fleet before version 3.5.1, due to issues in Go's standard library XML parsing, a valid SAML response may be mutated by an attacker to modify the trusted document. This can result in allowing unverified logins from a SAML IdP. Users that configure Fleet with SSO login may be vulnerable to this issue. This issue is patched in 3.5.1. The fix was made using https://github.com/mattermost/xml-roundtrip-validator If upgrade to 3.5.1 is not possible, users should disable SSO authentication in Fleet.
Affected configurations
• fleetdm fleet (< 3.5.1)
Related
Weakness · CWE (1)
- CWE-290 Authentication Bypass by Spoofing weakness
References
- https://github.com/fleetdm/fleet/blob/master/CHANGELOG.md#fleet-351-dec-14-2020 Release Notes, Third Party Advisory
- https://github.com/fleetdm/fleet/commit/57812a532e5f749c8e18c6f6a652eca65c083607 Patch, Third Party Advisory
- https://github.com/fleetdm/fleet/security/advisories/GHSA-w3wf-cfx3-6gcx Third Party Advisory
- https://github.com/mattermost/xml-roundtrip-validator Third Party Advisory
- https://mattermost.com/blog/coordinated-disclosure-go-xml-vulnerabilities Not Applicable, Third Party Advisory
- https://github.com/fleetdm/fleet/blob/master/CHANGELOG.md#fleet-351-dec-14-2020 Release Notes, Third Party Advisory
- https://github.com/fleetdm/fleet/commit/57812a532e5f749c8e18c6f6a652eca65c083607 Patch, Third Party Advisory
- https://github.com/fleetdm/fleet/security/advisories/GHSA-w3wf-cfx3-6gcx Third Party Advisory
- https://github.com/mattermost/xml-roundtrip-validator Third Party Advisory
- https://mattermost.com/blog/coordinated-disclosure-go-xml-vulnerabilities Not Applicable, Third Party Advisory