// For flags

CVE-2016-4553

squid: Cache poisoning issue in HTTP Request handling

Severity Score

8.6
*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

client_side.cc in Squid before 3.5.18 and 4.x before 4.0.10 does not properly ignore the Host header when absolute-URI is provided, which allows remote attackers to conduct cache-poisoning attacks via an HTTP request.

client_side.cc en Squid en versiones anteriores a 3.5.18 y 4.x en versiones anteriores a 4.0.10 no ignora correctamente la cabecera Host cuando se proporciona una URI absoluta, lo que permite a atacantes remotos llevar a cabo ataques de envenenamiento de caché a través de una petición HTTP.

An input validation flaw was found in the way Squid handled intercepted HTTP Request messages. An attacker could use this flaw to bypass the protection against issues related to CVE-2009-0801, and perform cache poisoning attacks on Squid.

Squid is a high-performance proxy caching server for web clients, supporting FTP, Gopher, and HTTP data objects. Security Fix: A buffer overflow flaw was found in the way the Squid cachemgr.cgi utility processed remotely relayed Squid input. When the CGI interface utility is used, a remote attacker could possibly use this flaw to execute arbitrary code. Buffer overflow and input validation flaws were found in the way Squid processed ESI responses. If Squid was used as a reverse proxy, or for TLS/HTTPS interception, a remote attacker able to control ESI components on an HTTP server could use these flaws to crash Squid, disclose parts of the stack memory, or possibly execute arbitrary code as the user running Squid.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
None
Integrity
High
Availability
None
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
Partial
Availability
None
Attack Vector
Network
Attack Complexity
Medium
Authentication
None
Confidentiality
None
Integrity
Partial
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2016-05-06 CVE Reserved
  • 2016-05-10 CVE Published
  • 2024-08-06 CVE Updated
  • 2025-03-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-20: Improper Input Validation
  • CWE-345: Insufficient Verification of Data Authenticity
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Canonical
Search vendor "Canonical"
Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
12.04
Search vendor "Canonical" for product "Ubuntu Linux" and version "12.04"
lts
Affected
Canonical
Search vendor "Canonical"
Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
14.04
Search vendor "Canonical" for product "Ubuntu Linux" and version "14.04"
lts
Affected
Canonical
Search vendor "Canonical"
Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
15.10
Search vendor "Canonical" for product "Ubuntu Linux" and version "15.10"
-
Affected
Canonical
Search vendor "Canonical"
Ubuntu Linux
Search vendor "Canonical" for product "Ubuntu Linux"
16.04
Search vendor "Canonical" for product "Ubuntu Linux" and version "16.04"
lts
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
<= 3.5.17
Search vendor "Squid-cache" for product "Squid" and version " <= 3.5.17"
-
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
4.0.1
Search vendor "Squid-cache" for product "Squid" and version "4.0.1"
-
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
4.0.2
Search vendor "Squid-cache" for product "Squid" and version "4.0.2"
-
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
4.0.3
Search vendor "Squid-cache" for product "Squid" and version "4.0.3"
-
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
4.0.4
Search vendor "Squid-cache" for product "Squid" and version "4.0.4"
-
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
4.0.5
Search vendor "Squid-cache" for product "Squid" and version "4.0.5"
-
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
4.0.6
Search vendor "Squid-cache" for product "Squid" and version "4.0.6"
-
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
4.0.7
Search vendor "Squid-cache" for product "Squid" and version "4.0.7"
-
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
4.0.8
Search vendor "Squid-cache" for product "Squid" and version "4.0.8"
-
Affected
Squid-cache
Search vendor "Squid-cache"
Squid
Search vendor "Squid-cache" for product "Squid"
4.0.9
Search vendor "Squid-cache" for product "Squid" and version "4.0.9"
-
Affected
Oracle
Search vendor "Oracle"
Linux
Search vendor "Oracle" for product "Linux"
7
Search vendor "Oracle" for product "Linux" and version "7"
-
Affected