Vulnerability Report

CVE-2016-4555

Title: Squid-Cache Squid Denial of Service (DoS)

DoS

Proof Of Concept

No public PoC currently indexed for CVE-2016-4555.

CWE Category CWE-20

Published Date May 10, 2016

Modified Date Jun 17, 2026

Exploit Status Not Found

Score 7.5 CVSS v3.0

Exploit Probability (EPSS)

53.92%

Vulnerability Summary

CVE-2016-4555: client_side_request.cc in Squid 3.x before 3.5.18 and 4.x before 4.0.10 allows remote servers to cause a denial of service (crash) via crafted Edge Side Includes (ESI) responses.

Impacted Vendors

squid 1

squid-cache 1

Reference Links

http://bugs.squid-cache.org/show_bug.cgi?id=4455 http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00010.html http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00040.html http://lists.opensuse.org/opensuse-updates/2016-08/msg00069.html http://www.debian.org/security/2016/dsa-3625 http://www.openwall.com/lists/oss-security/2016/05/06/3 http://www.openwall.com/lists/oss-security/2016/05/06/5 http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html http://www.securitytracker.com/id/1035770 http://www.squid-cache.org/Advisories/SQUID-2016_9.txt http://www.squid-cache.org/Versions/v3/3.4/changesets/SQUID-2016_9.patch http://www.squid-cache.org/Versions/v3/3.5/changesets/SQUID-2016_9.patch http://www.ubuntu.com/usn/USN-2995-1 https://access.redhat.com/errata/RHSA-2016:1139 https://access.redhat.com/errata/RHSA-2016:1140 https://security.gentoo.org/glsa/201607-01 http://bugs.squid-cache.org/show_bug.cgi?id=4455 http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00010.html http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00040.html http://lists.opensuse.org/opensuse-updates/2016-08/msg00069.html http://www.debian.org/security/2016/dsa-3625 http://www.openwall.com/lists/oss-security/2016/05/06/3 http://www.openwall.com/lists/oss-security/2016/05/06/5 http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html http://www.securitytracker.com/id/1035770 http://www.squid-cache.org/Advisories/SQUID-2016_9.txt http://www.squid-cache.org/Versions/v3/3.4/changesets/SQUID-2016_9.patch http://www.squid-cache.org/Versions/v3/3.5/changesets/SQUID-2016_9.patch http://www.ubuntu.com/usn/USN-2995-1 https://access.redhat.com/errata/RHSA-2016:1139 https://access.redhat.com/errata/RHSA-2016:1140 https://security.gentoo.org/glsa/201607-01

CVSS v3.0

Source Entity [email protected]

Severity HIGH

7.5

Attack Vector

NETWORK

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

RAW VECTOR CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS v2.0

Source Entity [email protected]

Severity MEDIUM

5.0

Access Vector

N/A

Authentication

N/A

RAW VECTOR AV:N/AC:L/Au:N/C:N/I:N/A:P

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2016-4555 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

June 17, 2026 MODIFIED

Vulnerability data updated via NVD.

May 06, 2026 MODIFIED

Vulnerability data updated via NVD.

April 12, 2025 MODIFIED

Vulnerability data or affected products updated.

May 10, 2016 PUBLISHED

Vulnerability first announced in NVD.

Attack Vector Matrix

Access Vector NETWORK

Complexity LOW

Privileges N/A

Interaction NONE

CVSS Vector String


                                    CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected Stack

No specific products linked.