CVE-2021-43999

Name: CVE-2021-43999
Creator: NVD / NIST
Published: 2022-01-11T22:15:07.627+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 1.78%

Last modified Jun 17, 2026

CVE-2021-43999 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. Apache Guacamole 1.2.0 and 1.3.0 do not properly validate responses received from a SAML identity provider. If SAML support is enabled, this may allow a malicious user to assume the identity of another Guacamole user.. EPSS estimates a 1.78% chance of exploitation in the next 30 days.

Description

Apache Guacamole 1.2.0 and 1.3.0 do not properly validate responses received from a SAML identity provider. If SAML support is enabled, this may allow a malicious user to assume the identity of another Guacamole user.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

1.78%

75.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Apache	Guacamole	1.2.0
Apache	Guacamole	1.3.0

References

http://www.openwall.com/lists/oss-security/2022/01/11/7Mailing List, Third Party Advisory
https://lists.apache.org/thread/4dt9h5mo4o9rxlgxm3rp8wfqdtdjn2z9Mailing List, Vendor Advisory
http://www.openwall.com/lists/oss-security/2022/01/11/7Mailing List, Third Party Advisory
https://lists.apache.org/thread/4dt9h5mo4o9rxlgxm3rp8wfqdtdjn2z9Mailing List, Vendor Advisory

Timeline

Published: Jan 11, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-43999?

How severe is CVE-2021-43999?

CVE-2021-43999 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 1.78% probability of exploitation in the next 30 days.

How do I fix CVE-2021-43999?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-43999?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST