2021-39241 | HAProxy HTTP Method admin access control
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A vulnerability was found in HAProxy up to 12.0.23/2.2.15/2.3.12/2.4.2 (Firewall Software). It has been rated as critical. This issue affects an unknown code block of the file /admin of the component HTTP Method Handler. The manipulation with an unknown input leads to a privilege escalation vulnerability. Using CWE to declare the problem leads to CWE-284. Impacted is confidentiality, integrity, and availability. The summary by CVE is:
An issue was discovered in HAProxy 2.0 before 2.0.24, 2.2 before 2.2.16, 2.3 before 2.3.13, and 2.4 before 2.4.3. An HTTP method name may contain a space followed by the name of a protected resource. It is possible that a server would interpret this as a request for that protected resource, such as in the “GET /admin? HTTP/1.1 /static/images HTTP/1.1” example.
The weakness was published 08/18/2021. The advisory is shared at mail-archive.com. The identification of this vulnerability is CVE-2021-39241 since 08/17/2021. The exploitation is known to be easy. The attack may be initiated remotely. The requirement for exploitation is a simple authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1068 for this issue.
Upgrading to version 2.0.24, 2.2.16, 2.3.13 or 2.4.3 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.haproxy.org. The best possible mitigation is suggested to be upgrading to the latest version.
VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0
Status: Not defined
0-Day Time: 🔒
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