#VU56679 Buffer overflow in Apache HTTP Server

Published: 2021-09-17

Vulnerability identifier: #VU56679

Vulnerability risk: Medium


CVE-ID: CVE-2021-39275


Exploitation vector: Network

Exploit availability:

Vulnerable software:
Apache HTTP Server
Server applications / Web servers

Vendor: Apache Foundation


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

Install updates from vendor's website.

Vulnerable software versions

Apache HTTP Server: 2.4.0 - 2.4.48

Fixed software versions


External links

Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?

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