CVE-2020-26276

SAML authentication vulnerability in Fleet

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.

Category

10.0
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.98% Top 25%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory mattermost.com
Affected: fleetdm fleet
Published at:
Updated at:

References

Link Tags
https://github.com/fleetdm/fleet/security/advisories/GHSA-w3wf-cfx3-6gcx third party advisory
https://github.com/fleetdm/fleet/commit/57812a532e5f749c8e18c6f6a652eca65c083607 third party advisory patch
https://github.com/fleetdm/fleet/blob/master/CHANGELOG.md#fleet-351-dec-14-2020 third party advisory release notes
https://github.com/mattermost/xml-roundtrip-validator third party advisory
https://mattermost.com/blog/coordinated-disclosure-go-xml-vulnerabilities third party advisory not applicable

Frequently Asked Questions

What is the severity of CVE-2020-26276?
CVE-2020-26276 has been scored as a critical severity vulnerability.
How to fix CVE-2020-26276?
To fix CVE-2020-26276, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-26276 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-26276 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-26276?
CVE-2020-26276 affects fleetdm fleet.
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