#VU42707 Stack-based buffer overflow in nginx - CVE-2013-2028

Vulnerability identifier: #VU42707

Vulnerability risk: Medium

CVSSv4.0: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:A/U:Green]

CVE-ID: CVE-2013-2028

CWE-ID: CWE-121

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
nginx
Server applications / Web servers

Vendor: NGINX

Description

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

The vulnerability exists due to a boundary error within the ngx_http_parse_chunked function in http/ngx_http_parse.c when processing a chunked Transfer-Encoding request with a large chunk size, which triggers an integer signedness error and a stack-based buffer overflow. A remote unauthenticated attacker can trigger stack-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
Install update from vendor's website.

Vulnerable software versions

nginx: 1.3.9, 1.4.0

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External links
https://lists.fedoraproject.org/pipermail/package-announce/2013-May/105176.html
https://mailman.nginx.org/pipermail/nginx-announce/2013/000112.html
https://nginx.org/download/patch.2013.chunked.txt
https://packetstormsecurity.com/files/121675/Nginx-1.3.9-1.4.0-Denial-Of-Service.html
https://secunia.com/advisories/55181
https://security.gentoo.org/glsa/glsa-201310-04.xml
https://www.osvdb.org/93037
https://www.securityfocus.com/bid/59699
https://www.vnsecurity.net/2013/05/analysis-of-nginx-cve-2013-2028/
https://github.com/rapid7/metasploit-framework/pull/1834

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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. However, a fully functional exploit for this vulnerability is available.