Vulnerability identifier: #VU56679

Vulnerability risk: Medium

CVSSv3.1: 4.9 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-39275

CWE-ID: CWE-119

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Apache HTTP Server
Server applications / Web servers

Vendor: Apache Foundation

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system or perform a denial of service attack.

The vulnerability exists due to a boundary error within the ap_escape_quotes()  function. A remote attacker can send a specially crafted request to the web server, trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system but requires that the Apache module passes untrusted data to the affected function.

According to vendor, No included modules pass untrusted data to these functions

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Apache HTTP Server: 2.4.0 - 2.4.48

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External links
http://httpd.apache.org/security/vulnerabilities_24.html

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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?

No. We are not aware of malware exploiting this vulnerability.