CVE-2019-18678 Information

Description

An issue was discovered in Squid 3.x and 4.x through 4.8. It allows attackers to smuggle HTTP requests through frontend software to a Squid instance that splits the HTTP Request pipeline differently. The resulting Response messages corrupt caches (between a client and Squid) with attacker-controlled content at arbitrary URLs. Effects are isolated to software between the attacker client and Squid. There are no effects on Squid itself nor on any upstream servers. The issue is related to a request header containing whitespace between a header name and a colon.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Reference

http://www.squid-cache.org/Advisories/SQUID-2019_10.txt http://www.squid-cache.org/Versions/v4/changesets/squid-4-671ba97abe929156dc4c717ee52ad22fba0f7443.patch https://bugzilla.suse.com/show_bug.cgi?id=1156323 https://github.com/squid-cache/squid/pull/445 https://lists.debian.org/debian-lts-announce/2019/12/msg00011.html https://lists.debian.org/debian-lts-announce/2020/07/msg00009.html https://lists.fedoraproject.org/archives/list/[email protected]/message/MTM74TU2BSLT5B3H4F3UDW53672NVLMC/ https://lists.fedoraproject.org/archives/list/[email protected]/message/UEMOYTMCCFWK5NOXSXEIH5D2VGWVXR67/ https://security.gentoo.org/glsa/202003-34 https://usn.ubuntu.com/4213-1/ https://www.debian.org/security/2020/dsa-4682

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

LOW

Base Score

NONE

Base Severity

5.3