CVE-2020-26276
published 2020-12-17CVE-2020-26276: 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…
PriorityP355critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
2.17%
80.0th percentile
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
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| fleetdm | fleet | < 3.5.1 | 3.5.1 |
| github.com | fleetdm_fleet_v4 | >= 0 < 3.5.1 | 3.5.1 |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P
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OSV
SAML authentication vulnerability due to stdlib XML parsing
osv·2022-02-11
CVE-2020-26276 [HIGH] SAML authentication vulnerability due to stdlib XML parsing
SAML authentication vulnerability due to stdlib XML parsing
### 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:
* Ema
GHSA
SAML authentication vulnerability due to stdlib XML parsing
ghsa·2022-02-11
CVE-2020-26276 [HIGH] CWE-290 SAML authentication vulnerability due to stdlib XML parsing
SAML authentication vulnerability due to stdlib XML parsing
### 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:
* Ema
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://github.com/fleetdm/fleet/blob/master/CHANGELOG.md#fleet-351-dec-14-2020https://github.com/fleetdm/fleet/commit/57812a532e5f749c8e18c6f6a652eca65c083607https://github.com/fleetdm/fleet/security/advisories/GHSA-w3wf-cfx3-6gcxhttps://github.com/mattermost/xml-roundtrip-validatorhttps://mattermost.com/blog/coordinated-disclosure-go-xml-vulnerabilitieshttps://github.com/fleetdm/fleet/blob/master/CHANGELOG.md#fleet-351-dec-14-2020https://github.com/fleetdm/fleet/commit/57812a532e5f749c8e18c6f6a652eca65c083607https://github.com/fleetdm/fleet/security/advisories/GHSA-w3wf-cfx3-6gcxhttps://github.com/mattermost/xml-roundtrip-validatorhttps://mattermost.com/blog/coordinated-disclosure-go-xml-vulnerabilities
2020-12-17
Published