#VU56678 Server-Side Request Forgery (SSRF)

Published: 2021-10-18 | Updated: 2022-08-07

Vulnerability identifier: #VU56678

Vulnerability risk: High


CVE-ID: CVE-2021-40438


Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
Apache HTTP Server
Server applications / Web servers

Vendor: Apache Foundation


The disclosed vulnerability allows a remote attacker to perform SSRF attacks.

The vulnerability exists due to insufficient validation of user-supplied input within the mod_proxy module in Apache HTTP Server. A remote attacker can send a specially crafted HTTP request with a chosen uri-path and trick the web server to initiate requests to arbitrary systems.

Successful exploitation of this vulnerability may allow a remote attacker gain access to sensitive data, located in the local network or send malicious requests to other servers from the vulnerable system.

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Vulnerable software versions

Apache HTTP Server: 2.4.0 - 2.4.48


External links

Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?

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