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Apache HTTP Server ap_pregsub() buffer overflow

Disclosed November 2, 2011    Fully Patched

Vulnerability Description:

There is an integer overflow vulnerability in the ap_pregsub function of the Apache Web server.  This integer overflow can lead to a buffer overflow and allow an attacker to execute arbitrary code.  The Apache Web server runs with elevated privileges, an attacker would need to exploit this locally but would gain elevated privileges on the machine.


Apache Software Foundation

Vulnerable Software/Devices:

Apache HTTP Server 2.2.21 and earlier

Vulnerability Severity:


Exploit Availability:


Exploit Impact:

Elevation of Privilege
Local Elevation of Privilege to root privileges This local vulnerability allows an attacker with file write privileges to run arbitrary code under the context of the Apache Server.

BeyondTrust Prevention and Detection:

BeyondTrust's Retina® Network Security Scanner scans devices to detect for this vulnerability.
  •  15584 - Apache Mod_SetEnvIf .htaccess Privilege Escalation


Disable the use of ".htaccess" on all locations that are writable by normal users.




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