Squid Cache Squid vulnerabilities
112 vulnerabilities
Known vulnerabilities in Squid Cache Squid, newest first, with CVSS severity, EPSS, KEV listings, ransomware use and the affected versions.
CVE-2026-61642debiansquid+3
EPSS score4.68%
Squid is a caching proxy for the Web. From 3.3.0.1 to before 7.6, due to an improper enforcement of behavioral workflow bug, Squid is vulnerable to a Request Smuggling attack against HTTP/1.1 Transfer-Encoding. HTTP header parsing (`src/HttpHeader.cc`) accepted the bare` Transfer-Encoding:` identity form, which the HTTP specification prohibits because any transfer coding must be wrapped within chunked encoding. This problem allows a trusted client to perform an HTTP Request Smuggling attack when HTTP/1.1 is used, bypassing security mechanisms that may be in place between attacker and Squid. When there is an HTTP cache operating prior to the affected Squid, this Request Smuggling attack also allows the attacker to poison that web cache and store arbitrary malicious content at any URL for delivery to other clients' future requests. This issue is fixed in version 7.6.CVE-2018-1172alpinesquid+7EPSS score8.31%
This vulnerability allows remote attackers to deny service on vulnerable installations of The Squid Software Foundation Squid 3.5.27-20180318. Authentication is not required to exploit this vulnerability. The specific flaw exists within ClientRequestContext::sslBumpAccessCheck(). A crafted request can trigger the dereference of a null pointer. An attacker can leverage this vulnerability to create a denial-of-service condition to users of the system. Was ZDI-CAN-6088.CVE-2018-1000027alpinesquid+5EPSS score12.91%
The Squid Software Foundation Squid HTTP Caching Proxy version prior to version 4.0.23 contains a NULL Pointer Dereference vulnerability in HTTP Response X-Forwarded-For header processing that can result in Denial of Service to all clients of the proxy. This attack appear to be exploitable via Remote HTTP server responding with an X-Forwarded-For header to certain types of HTTP request. This vulnerability appears to have been fixed in 4.0.23 and later.CVE-2018-1000024alpinesquid+5EPSS score7.93%
The Squid Software Foundation Squid HTTP Caching Proxy version 3.0 to 3.5.27, 4.0 to 4.0.22 contains a Incorrect Pointer Handling vulnerability in ESI Response Processing that can result in Denial of Service for all clients using the proxy.. This attack appear to be exploitable via Remote server delivers an HTTP response payload containing valid but unusual ESI syntax.. This vulnerability appears to have been fixed in 4.0.23 and later.CVE-2018-19132debiansquid+4EPSS score6.11%
Squid before 4.4, when SNMP is enabled, allows a denial of service (Memory Leak) via an SNMP packet.CVE-2018-19131debiansquid+3EPSS score3.32%
Squid before 4.4 has XSS via a crafted X.509 certificate during HTTP(S) error page generation for certificate errors.CVE-2013-1839squid-cachesquidEPSS score18.31%
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.CVE-2013-0189canonicalubuntu_linux+2EPSS score23.03%
cachemgr.cgi in Squid 3.1.x and 3.2.x, possibly 3.1.22, 3.2.4, and other versions, allows remote attackers to cause a denial of service (resource consumption) via a crafted request. NOTE: this issue is due to an incorrect fix for CVE-2012-5643, possibly involving an incorrect order of arguments or incorrect comparison.CVE-2013-4115mageiasquid+2EPSS score43.90%
Buffer overflow in the idnsALookup function in dns_internal.cc in Squid 3.2 through 3.2.11 and 3.3 through 3.3.6 allows remote attackers to cause a denial of service (memory corruption and server termination) via a long name in a DNS lookup request.CVE-2013-4123opensuseopensuse+1EPSS score80.45%
client_side_request.cc in Squid 3.2.x before 3.2.13 and 3.3.x before 3.3.8 allows remote attackers to cause a denial of service via a crafted port number in a HTTP Host header.CVE-2021-41611alpinesquid+3EPSS score2.95%
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.CVE-2021-31808alpinesquid+7EPSS score5.34%
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.CVE-2021-31807alpinesquid+6EPSS score15.56%
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.CVE-2021-31806alpinesquid+7EPSS score95.33%
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.CVE-2021-46784debiansquid+17EPSS score5.13%
In Squid 3.x through 3.5.28, 4.x through 4.17, and 5.x before 5.6, due to improper buffer management, a Denial of Service can occur when processing long Gopher server responses.CVE-2021-28662alpinesquid+5EPSS score71.76%
An issue was discovered in Squid 4.x before 4.15 and 5.x before 5.0.6. If a remote server sends a certain response header over HTTP or HTTPS, there is a denial of service. This header can plausibly occur in benign network traffic.CVE-2021-28116alpinesquid+21EPSS score12.95%
Squid through 4.14 and 5.x through 5.0.5, in some configurations, allows information disclosure because of an out-of-bounds read in WCCP protocol data. This can be leveraged as part of a chain for remote code execution as nobody.CVE-2021-28651alpinesquid+7EPSS score7.45%
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.CVE-2021-28652alpinesquid+6EPSS score4.34%
An issue was discovered in Squid before 4.15 and 5.x before 5.0.6. Due to incorrect parser validation, it allows a Denial of Service attack against the Cache Manager API. This allows a trusted client to trigger memory leaks that. over time, lead to a Denial of Service via an unspecified short query string. This attack is limited to clients with Cache Manager API access privilege.CVE-2021-33620alpinesquid+7EPSS score79.58%
Squid before 4.15 and 5.x before 5.0.6 allows remote servers to cause a denial of service (affecting availability to all clients) via an HTTP response. The issue trigger is a header that can be expected to exist in HTTP traffic without any malicious intent by the server.