CVE-2019-18277
HIGHEPSS 95th pctlDescription
A flaw was found in HAProxy before 2.0.6. In legacy mode, messages featuring a transfer-encoding header missing the "chunked" value were not being correctly rejected. The impact was limited but if combined with the "http-reuse always" setting, it could be used to help construct an HTTP request smuggling attack against a vulnerable component employing a lenient parser that would ignore the content-length header as soon as it saw a transfer-encoding one (even if not entirely valid according to the specification).
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Exploit Intelligence
Very high risk: more likely to be exploited than 95% of all known CVEs.
References
- http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00016.html
- http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00019.html
- https://git.haproxy.org/?p=haproxy-2.0.git%3Ba=commit%3Bh=196a7df44d8129d1adc795da020b722614d6a581
- https://lists.debian.org/debian-lts-announce/2022/05/msg00045.html
- https://nathandavison.com/blog/haproxy-http-request-smuggling
- https://usn.ubuntu.com/4174-1/
- https://www.mail-archive.com/haproxy%40formilux.org/msg34926.html
Find and fix vulnerabilities across your fleet
TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.
Start freeThis product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.