Heap-based buffer overflow in Apache HTTP Server

Published: 2011-11-08 | Updated: 2020-07-28

Risk	Medium
Patch available	YES
Number of vulnerabilities	1
CVE-ID	CVE-2011-3607
CWE-ID	CWE-122
Exploitation vector	Local
Public exploit	Public exploit code for vulnerability #1 is available.
Vulnerable software Subscribe	Apache HTTP Server Server applications / Web servers
Vendor	Apache Foundation

Security Bulletin

This security bulletin contains one medium risk vulnerability.

1) Heap-based buffer overflow

EUVDB-ID: #VU32830

Risk: Medium

CVSSv3.1: 5.3 [CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C]

CVE-ID: CVE-2011-3607

CWE-ID: CWE-122 - Heap-based Buffer Overflow

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in Integer overflow in the ap_pregsub function in server/util.c in the Apache HTTP Server 2.0.x through 2.0.64 and 2.2.x through 2.2.21, when the mod_setenvif module is enabled,. A remote attacker can use a .htaccess file with a crafted SetEnvIf directive to trigger heap-based buffer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation

Update to version 2.0.65.

Vulnerable software versions

Apache HTTP Server: 2.0.11 - 2.0.64

External links

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

The attacker would have to login to the system and perform certain actions in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.