Critical severity · published Dec 17, 2020
CVE-2020-26276
Fleet is an open source osquery manager
9.8
CVSS
2.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.2% · higher than 82% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FL
Fleet · Fleetdm
before 3.5.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-26276
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-26276
Release Notes
https://github.com/fleetdm/fleet/blob/master/CHANGELOG.md#fleet-351-dec-14-2020
Patch
https://github.com/fleetdm/fleet/commit/57812a532e5f749c8e18c6f6a652eca65c083607
Third Party Advisory
https://github.com/fleetdm/fleet/security/advisories/GHSA-w3wf-cfx3-6gcx
Third Party Advisory
https://github.com/mattermost/xml-roundtrip-validator
Not Applicable
https://mattermost.com/blog/coordinated-disclosure-go-xml-vulnerabilities
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