Amazon Linux AMI update for lighttpd

1) Input validation error

EUVDB-ID: #VU33958

Risk: Medium

CVSSv4.0: 5.5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2011-4362

CWE-ID: CWE-20 - Improper input validation

Exploit availability: Yes

Description

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

Integer signedness error in the base64_decode function in the HTTP authentication functionality (http_auth.c) in lighttpd 1.4 before 1.4.30 and 1.5 before SVN revision 2806 allows remote attackers to cause a denial of service (segmentation fault) via crafted base64 input that triggers an out-of-bounds read with a negative index.

Mitigation

Update the affected packages:

i686:
    lighttpd-fastcgi-1.4.31-1.2.amzn1.i686
    lighttpd-mod_mysql_vhost-1.4.31-1.2.amzn1.i686
    lighttpd-debuginfo-1.4.31-1.2.amzn1.i686
    lighttpd-mod_geoip-1.4.31-1.2.amzn1.i686
    lighttpd-1.4.31-1.2.amzn1.i686

src:
    lighttpd-1.4.31-1.2.amzn1.src

x86_64:
    lighttpd-fastcgi-1.4.31-1.2.amzn1.x86_64
    lighttpd-debuginfo-1.4.31-1.2.amzn1.x86_64
    lighttpd-1.4.31-1.2.amzn1.x86_64
    lighttpd-mod_geoip-1.4.31-1.2.amzn1.x86_64
    lighttpd-mod_mysql_vhost-1.4.31-1.2.amzn1.x86_64

Vulnerable software versions

Amazon Linux AMI: All versions

CPE2.3

• cpe:2.3:o:amazon_web_services:amazon_linux_ami:*:*:*:*:*:*:*:*

External links

https://alas.aws.amazon.com/ALAS-2012-107.html

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, proof of concept for this vulnerability is available.