Where
-Infinity
0
Severity
8.8
Buffer Overflow
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Buffer overflow in cachemgr.cgi in Squid 2.x, 3.x before 3.5.17, and 4.x before 4.0.9 might allow remote attackers to cause a denial of service or execute arbitrary code by seeding manager reports with crafted data.

1 / 2
Source: MITRE
First published (updated )
Severity
8.6
EPSS
0.04%
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Last updated 28 February 2025

1 / 3
Source: Ubuntu
First published (updated )
Severity
8.6
Input Validation
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

Due to incorrect input validation Squid is vulnerable to a header smuggling attack leading to cache poisoning and to bypass of same-origin security policy in Squid and some client browsers.

External references:

http://www.squid-cache.org/Advisories/SQUID-20168.txt

Upstream fixes:

[RHEL-7]:

http://www.squid-cache.org/Versions/v3/3.3/changesets/SQUID-20168.patch>

[RHEL-6]:

http://www.squid-cache.org/Versions/v3/3.1/changesets/SQUID-20168.patch

[Fedora-22]:

http://www.squid-cache.org/Versions/v3/3.4/changesets/SQUID-20168.patch

[Fedora-23]:

http://www.squid-cache.org/Versions/v3/3.5/changesets/SQUID-20168.patch

1 / 2
Source: Red Hat
First published (updated )
Severity
8.6
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

clientside.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.

1 / 2
Source: MITRE
First published (updated )
Severity
8.6
Input Validation
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

An issue was discovered in Squid through 4.13 and 5.x through 5.0.4. Due to improper input validation, it allows a trusted client to perform HTTP Request Smuggling and access services otherwise forbidden by the security controls. This occurs for certain uriwhitespace configuration settings.

1 / 2
First published (updated )
Severity
8.6
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

A buffer over-read was discovered in libntlmauth in Squid 2.5 through 5.6. Due to incorrect integer-overflow protection, the SSPI and SMB authentication helpers are vulnerable to reading unintended memory locations. In some configurations, cleartext credentials from these locations are sent to a client. This is fixed in 5.7.

1 / 2
First published (updated )
Severity
8.6
Out-of-bounds Read
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Squid is a caching proxy for the Web. Due to an Improper Validation of Specified Index bug, Squid versions 3.3.0.1 through 5.9 and 6.0 prior to 6.4 compiled using --with-openssl are vulnerable to a Denial of Service attack against SSL Certificate validation. This problem allows a remote server to perform Denial of Service against Squid Proxy by initiating a TLS Handshake with a specially crafted SSL Certificate in a server certificate chain. This attack is limited to HTTPS and SSL-Bump. This bug is fixed in Squid version 6.4. In addition, patches addressing this problem for the stable releases can be found in Squid's patch archives. Those who you use a prepackaged version of Squid should refer to the package vendor for availability information on updated packages.

1 / 3
Source: Ubuntu
First published (updated )
Severity
8.6
Use After Free
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Last updated 24 July 2024

1 / 2
Source: Ubuntu
First published (updated )
Severity
8.6
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Last updated 24 July 2024

1 / 3
Source: Ubuntu
First published (updated )
Severity
8.6
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Last updated 24 July 2024

1 / 3
Source: Ubuntu
First published (updated )
Severity
8.6
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Last updated 24 July 2024

1 / 3
Source: Ubuntu
First published (updated )
Severity
8.2
Buffer Overflow
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

Heap-based buffer overflow in the Icmp6::Recv function in icmp/Icmp6.cc in the pinger utility in Squid before 3.5.16 and 4.x before 4.0.8 allows remote servers to cause a denial of service (performance degradation or transition failures) or write sensitive information to log files via an ICMPv6 packet.

First published (updated )
Severity
8.1
Buffer Overflow, Input Validation
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Due to buffer overflow issues Squid is vulnerable to a denial of service attack when processing ESI responses.

Due to incorrect input validation Squid is vulnerable to public information disclosure of the server stack layout when processing ESI responses.

Due to incorrect input validation and buffer overflow Squid is vulnerable to remote code execution when processing ESI responses.

External references:

http://www.squid-cache.org/Advisories/SQUID-20166.txt

Upstream fix:

[RHEL-7] http://www.squid-cache.org/Versions/v3/3.3/changesets/squid-3.3-12697.patch

[Fedora-22] http://www.squid-cache.org/Versions/v3/3.4/changesets/squid-3.4-13235.patch

[Fedora-23] http://www.squid-cache.org/Versions/v3/3.5/changesets/squid-3.5-14034.patch

1 / 2
Source: Red Hat
First published (updated )
Severity
8.1
Buffer Overflow
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Buffer overflow in Squid 3.x before 3.5.17 and 4.x before 4.0.9 allows remote attackers to execute arbitrary code via crafted Edge Side Includes (ESI) responses.

First published (updated )
Severity
7.8
Input Validation
AV:N/AC:L/Au:N/C:N/I:N/A:C

The strHdrAcptLangGetItem function in errorpage.cc in Squid 3.2.x before 3.2.9 and 3.3.x before 3.3.3 allows remote attackers to cause a denial of service (infinite loop and CPU consumption) via a "," character in an Accept-Language header.

First published (updated )
Severity
7.5
Input Validation
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to a buffer-management bug, it allows a denial of service. When resolving a request with the urn: scheme, the parser leaks a small amount of memory. However, there is an unspecified attack methodology that can easily trigger a large amount of memory consumption.

1 / 3
Source: Launchpad
First published (updated )
Severity
7.5
AV:N/AC:L/Au:N/C:P/I:P/A:P

Gibraltar Firewall 2.2 and earlier, when using the ClamAV update to 0.81 for Squid, uses a defunct ClamAV method to scan memory for viruses, which does not return an error code and prevents viruses from being detected.

First published (updated )
Severity
7.5
Input Validation
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

http.cc in Squid 4.x before 4.0.7 relies on the HTTP status code after a response-parsing failure, which allows remote HTTP servers to cause a denial of service (assertion failure and daemon exit) via a malformed response.

First published (updated )
Severity
7.5
Double Free
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Double free vulnerability in Esi.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 a crafted Edge Side Includes (ESI) response.

1 / 2
Source: MITRE
First published (updated )
Severity
7.5
Input Validation
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

clientsiderequest.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.

1 / 2
Source: MITRE
First published (updated )
Severity
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

An issue was discovered in Squid 5.0.6 through 5.1.x before 5.2. When validating an origin server or peer certificate, Squid may incorrectly classify certain certificates as trusted. This problem allows a remote server to obtain security trust well improperly. This indication of trust may be passed along to clients, allowing access to unsafe or hijacked services.

First published (updated )
Severity
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

An issue was discovered in Squid before 4.12 and 5.x before 5.0.3. Due to use of a potentially dangerous function, Squid and the default certificate validation helper are vulnerable to a Denial of Service when opening a TLS connection to an attacker-controlled server for HTTPS. This occurs because unrecognized error values are mapped to NULL, but later code expects that each error value is mapped to a valid error string.

First published (updated )
Severity
7.5
Null Pointer Dereference
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to a NULL pointer dereference bug Squid is vulnerable to a Denial of Service attack against Squid's Gopher gateway. The gopher protocol is always available and enabled in Squid prior to Squid 6.0.1. Responses triggering this bug are possible to be received from any gopher server, even those without malicious intent. Gopher support has been removed in Squid version 6.0.1. Users are advised to upgrade. Users unable to upgrade should reject all gopher URL requests.

1 / 3
Source: Ubuntu
First published (updated )
Severity
7
Input Validation

Squid is an open source caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to Input Validation, Premature Release of Resource During Expected Lifetime, and Missing Release of Resource after Effective Lifetime bugs, Squid is vulnerable to Denial of Service attacks by a trusted server against all clients using the proxy. This bug is fixed in the default build configuration of Squid version 6.10.

First published (updated )
Severity
6.8
Buffer Overflow
AV:N/AC:M/Au:N/C:P/I:P/A:P

A flaw was reported [1] in how Squid parsed responses from Gopher servers. This flaw could result in a buffer overflow if a Gopher server were to return a line longer than 4096 bytes, leading to memory corruption and a crash. This flaw is an extension of SQUID-2005:1 (or CVE-2005-0094) in Squid 3.x, due to increased packet read sizes. A malicious user could setup a fake Gopher server and forward requests to it through Squid. A specially crafted response from that server could cause Squid to restart.

This has been corrected in upstream versions 3.2.0.11, 3.1.15, and 3.0.STABLE26. Patches for 3.0 [2], 3.1 [3], and 3.2 [4] are available.

[1] http://www.squid-cache.org/Advisories/SQUID-20113.txt [2] http://www.squid-cache.org/Versions/v3/3.0/changesets/squid-3.0-9193.patch [3] http://www.squid-cache.org/Versions/v3/3.1/changesets/squid-3.1-10363.patch [4] http://www.squid-cache.org/Versions/v3/3.2/changesets/squid-3.2-11294.patch

1 / 3
Source: Red Hat
First published (updated )
Severity
6.8
Buffer Overflow
AV:N/AC:M/Au:N/C:P/I:P/A:P

Last updated 24 July 2024

1 / 3
Source: Ubuntu
First published (updated )
Severity
6.8
AV:N/AC:M/Au:N/C:P/I:P/A:P

Squid before 3.5.6 does not properly handle CONNECT method peer responses when configured with cachepeer, which allows remote attackers to bypass intended restrictions and gain access to a backend proxy via a CONNECT request.

First published (updated )
Severity
6.5
Input Validation
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to a memory-management bug, it is vulnerable to a Denial of Service attack (against all clients using the proxy) via HTTP Range request processing.

1 / 3
Source: Launchpad
First published (updated )
Severity
6.5
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to an input-validation bug, it is vulnerable to a Denial of Service attack (against all clients using the proxy). A client sends an HTTP Range request to trigger this.

1 / 3
Source: Launchpad
First published (updated )
Severity
6.5
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. An integer overflow problem allows a remote server to achieve Denial of Service when delivering responses to HTTP Range requests. The issue trigger is a header that can be expected to exist in HTTP traffic without any malicious intent.

1 / 3
Source: Launchpad
First published (updated )

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