CVE-2021-43999
Improper validation of SAML responses
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2021-43999- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 6.0 Medium
AV:N/AC:M/Au:S/C:P/I:P/A:P - Weakness
- CWE-287
- Updated
- 2026-11-02
CVE List No score
Improper validation of SAML responses
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.
- Record
CVE-2021-43999- Weakness
- CWE-287
- Updated
- 2026-11-02
EUVDEUVD-2021-30858 No score
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.
- Record
EUVD-2021-30858- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-v83c-8hcj-4545
Improper Authentication in Apache Guacamole
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.
- Record
GHSA-v83c-8hcj-4545- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-287
- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2021-43999- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-43999
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.
- Record
UBUNTU-CVE-2021-43999- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVBIT-guacamole-2021-43999 No score
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.
- Record
BIT-guacamole-2021-43999- Updated
- 2026-11-02
OSVBIT-guacamole-server-2021-43999 No score
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.
- Record
BIT-guacamole-server-2021-43999- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
guacamoleBitnami |
1.2.0 to 1.2.0, 1.3.0 to 1.3.0 | None known |
guacamole-serverBitnami |
1.2.0 to 1.2.0, 1.3.0 to 1.3.0 | None known |
guacamole-serverUbuntu:16.04:LTS |
All versions, plus listed versions 0.8.3-1build20.8.3-2 |
None known |
guacamole-serverUbuntu:18.04:LTS |
All versions, plus listed versions 0.9.9-20.9.9-2build1 |
None known |
guacamole-serverUbuntu:22.04:LTS |
All versions, plus listed versions 1.3.0-11.3.0-1build11.3.0-1.1 |
None known |
guacamole-serverUbuntu:24.04:LTS |
All versions, plus listed versions 1.3.0-1.11.3.0-1.3ubuntu1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-43999 is a high vulnerability (CVSS 8.8) in Apache Guacamole, published January 11, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.84%, the 79th percentile. No source names a fixed version.