This security advisory describes one medium risk vulnerability.
The vulnerability allows a remote attacker to perform HTTP request smuggling attack.
The vulnerability exists due to incorrect processing of messages with a missing transfer-encoding header, when HAProxy is configured in legacy mode. The server does not reject "chunked" value that combined with the "http-reuse always" setting can lead to HTTP request smuggling attack.
Update the affected packages.
haproxy (Ubuntu package): 1.6.3-1ubuntu0.1, 1.6.3-1ubuntu0.2, 1.8.8-1ubuntu0.1, 1.8.8-1ubuntu0.2, 1.8.8-1ubuntu0.3, 1.8.8-1ubuntu0.4, 1.8.8-1ubuntu0.5, 1.8.8-1ubuntu0.6, 1.8.19-1ubuntu1.1CPE
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.