Red Hat Enterprise Linux 8.2 update for the httpd:2.4 module

1) Server-Side Request Forgery (SSRF)

EUVDB-ID: #VU56678

Risk: High

CVSSv3.1: 8.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N/E:H/RL:O/RC:C]

CVE-ID: CVE-2021-40438

CWE-ID: CWE-918 - Server-Side Request Forgery (SSRF)

Exploit availability: Yes

Description

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.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux Server - TUS: 8.2

External links

http://access.redhat.com/errata/RHSA-2021:3836

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.