Vulnerability identifier: #VU32825

Vulnerability risk: Low

CVSSv3.1: 3.2 [CVSS:3.1/CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2012-0021

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Apache HTTP Server
Server applications / Web servers

Vendor: Apache Foundation

Description

The vulnerability allows a remote non-authenticated attacker to perform service disruption.

The log_cookie function in mod_log_config.c in the mod_log_config module in the Apache HTTP Server 2.2.17 through 2.2.21, when a threaded MPM is used, does not properly handle a %{}C format string, which allows remote attackers to cause a denial of service (daemon crash) via a cookie that lacks both a name and a value.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Apache HTTP Server: 2.2.17 - 2.2.21

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External links
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c03360041
http://httpd.apache.org/security/vulnerabilities_22.html
http://lists.apple.com/archives/security-announce/2012/Sep/msg00004.html
http://marc.info/?l=bugtraq&m=133294460209056&w=2
http://marc.info/?l=bugtraq&m=133494237717847&w=2
http://rhn.redhat.com/errata/RHSA-2012-0542.html
http://rhn.redhat.com/errata/RHSA-2012-0543.html
http://secunia.com/advisories/48551
http://support.apple.com/kb/HT5501
http://svn.apache.org/viewvc?view=revision&revision=1227292
http://www.mandriva.com/security/advisories?name=MDVSA-2012:012
http://www.mandriva.com/security/advisories?name=MDVSA-2013:150
http://www.oracle.com/technetwork/topics/security/cpujul2012-392727.html
http://bugzilla.redhat.com/show_bug.cgi?id=785065
http://issues.apache.org/bugzilla/show_bug.cgi?id=52256
http://lists.apache.org/thread.html/8d63cb8e9100f28a99429b4328e4e7cebce861d5772ac9863ba2ae6f@%3Ccvs.httpd.apache.org%3E
http://lists.apache.org/thread.html/f7f95ac1cd9895db2714fa3ebaa0b94d0c6df360f742a40951384a53@%3Ccvs.httpd.apache.org%3E
http://lists.apache.org/thread.html/r57608dc51b79102f3952ae06f54d5277b649c86d6533dcd6a7d201f7@%3Ccvs.httpd.apache.org%3E
http://lists.apache.org/thread.html/rfbaf647d52c1cb843e726a0933f156366a806cead84fbd430951591b@%3Ccvs.httpd.apache.org%3E

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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.