GHSA-w3wf-cfx3-6gcx
SAML authentication vulnerability due to stdlib XML parsing
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| Go | github.com/fleetdm/fleet/v4 | < 3.5.1 | 3.5.1 |
Details
As written in the advisory (Markdown source, shown as plain text).
### Impact
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.
### Patches
This issue is patched in 3.5.1 using https://github.com/mattermost/xml-roundtrip-validator.
### Workarounds
If upgrade to 3.5.1 is not possible, users should disable SSO authentication in Fleet.
### References
See https://mattermost.com/blog/coordinated-disclosure-go-xml-vulnerabilities/ for more information about the underlying vulnerabilities.
### For more information
If you have any questions or comments about this advisory:
* Email us at [[email protected]](mailto:[email protected])
* Join #fleet in [osquery Slack](https://join.slack.com/t/osquery/shared_invite/zt-h29zm0gk-s2DBtGUTW4CFel0f0IjTEw)
References
External links from the advisory. They lead to third-party sites.
- https://github.com/fleetdm/fleet/security/advisories/GHSA-w3wf-cfx3-6gcx
- https://nvd.nist.gov/vuln/detail/CVE-2020-26276
- https://github.com/fleetdm/fleet/commit/57812a532e5f749c8e18c6f6a652eca65c083607
- https://github.com/fleetdm/fleet/blob/master/CHANGELOG.md#fleet-351-dec-14-2020
- https://github.com/mattermost/xml-roundtrip-validator
- https://mattermost.com/blog/coordinated-disclosure-go-xml-vulnerabilities