PT-2019-6398 · Haproxy+5 · Haproxy+5

Emeric Brun · Published 2019-09-07 · Updated 2024-06-15 · CVE-2019-18277

Positive Technologies (AI Summary)

CVSS v2.0

7.8

High

Base vector

AV:N/AC:L/Au:N/C:N/I:C/A:N

Name of the Vulnerable Software and Affected Versions HAProxy versions prior to 2.0.6

Description A flaw was found in the handling of HTTP requests. The issue is related to messages featuring a transfer-encoding header missing the "chunked" value, which were not being correctly rejected in legacy mode. 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.

Recommendations For versions prior to 2.0.6, update to version 2.0.6 or later to resolve the issue. As a temporary workaround, consider avoiding the use of the "http-reuse always" setting in legacy mode until a patch is applied. Restrict access to components that employ lenient parsers to minimize the risk of exploitation.

Exploit

Fix

HTTP Request/Response Smuggling

Weakness Enumeration

CWE-444

Related Identifiers

ALT-PU-2019-2775

ALT-PU-2019-2777

BDU:2023-07810

CESA-2020_1725

CVE-2019-18277

DLA-3034-1

OPENSUSE-SU-2019:2626-1

OPENSUSE-SU-2019:2645-1

OPENSUSE-SU-2019_2626-1

OPENSUSE-SU-2019_2645-1

OPENSUSE-SU-2024:10839-1

RHSA-2020:1287

RHSA-2020:1725

RHSA-2020:1936

RHSA-2020:2265

RHSA-2020_1725

SUSE-SU-2019:3125-1

SUSE-SU-2019:3126-1

SUSE-SU-2019:3288-1

SUSE-SU-2019_3125-1

SUSE-SU-2019_3126-1

SUSE-SU-2019_3288-1

USN-4174-1

Affected Products

Alt Linux

Centos

Haproxy

Red Hat

Suse

Ubuntu

References · 73

• 🔥 https://nathandavison.com/blog/haproxy-http-request-smuggling · Exploit
• https://ubuntu.com/security/CVE-2019-18277 · Vendor Advisory
• http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00019.html · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-20103 · Security Note
• https://osv.dev/vulnerability/CVE-2019-18277 · Vendor Advisory
• http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00016.html · Vendor Advisory
• https://bdu.fstec.ru/vul/2023-07810 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2019-18277 · Security Note
• https://security-tracker.debian.org/tracker/source-package/haproxy · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2019:3125-1 · Vendor Advisory
• https://osv.dev/vulnerability/USN-4174-1 · Vendor Advisory
• https://bdu.fstec.ru/vul/2020-03308 · Security Note
• https://ubuntu.com/security/notices/USN-4174-1 · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-19330 · Security Note
• https://osv.dev/vulnerability/openSUSE-SU-2019:2626-1 · Vendor Advisory