CVE-2021-43999

HIGHNVD 8.88.8—

8.8

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.

CVSS v3: 8.8
EG Score: 8.8(medium)
EPSS: 80.5%
KEV: Not listed

Published

January 11, 2022

Last Modified

November 21, 2024

References (4)

security@apachehttp://www.openwall.com/lists/oss-security/2022/01/11/7
security@apachehttps://lists.apache.org/thread/4dt9h5mo4o9rxlgxm3rp8wfqdtdjn2z9
af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2022/01/11/7
af854a3a-2127-422b-91ae-364da2661108https://lists.apache.org/thread/4dt9h5mo4o9rxlgxm3rp8wfqdtdjn2z9

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-287Improper Authentication

Data Freshness Timeline

(refreshed 15× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

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Frequently asked(5)

What is CVE-2021-43999?

CVE-2021-43999 is a high vulnerability published on January 11, 2022. 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.

When was CVE-2021-43999 disclosed?

CVE-2021-43999 was first published in the National Vulnerability Database on January 11, 2022, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-43999 actively exploited?

CVE-2021-43999 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 80.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-43999?

CVE-2021-43999 has a CVSS v3 base score of 8.8 (NVD).

How do I remediate CVE-2021-43999?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-43999, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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CVE-2021-43999

📅 Published

🔄 Last Modified

🔗 References (4)

Weakness Classification(1)

Data Freshness Timeline

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2021-43999?

🔗 Related CVEs(same CWE)

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Published

Last Modified

References (4)

Frequently asked(5)

Related CVEs(same CWE)