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Squid

squid

Vendor: Squid Cache • 111 CVEs

CVEs (111)

CVE
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UPDATED
PUBLISHED
CVSS
2Redhat
Squid Cache
10Enterprise Linux
Enterprise Linux EusEnterprise Linux For Arm 64+7 more
Jun 17, 2026
Nov 3, 2023
N/A· v4
7.5 HIGH· v3
N/A· v2
Squid is vulnerable to a Denial of Service, where a remote attacker can perform buffer overflow attack by writing up to 2 MB of arbitrary data to heap memory when Squid is configured to accept HTTP Digest Authentication...Show more
Squid is vulnerable to a Denial of Service, where a remote attacker can perform buffer overflow attack by writing up to 2 MB of arbitrary data to heap memory when Squid is configured to accept HTTP Digest Authentication.Show less
2Redhat
Squid Cache
8Enterprise Linux
Enterprise Linux EusEnterprise Linux For Arm 64+5 more
Jun 17, 2026
Nov 3, 2023
N/A· v4
5.3 MEDIUM· v3
N/A· v2
SQUID is vulnerable to HTTP request smuggling, caused by chunked decoder lenience, allows a remote attacker to perform Request/Response smuggling past firewall and frontend security systems.
1Squid Cache
1Squid
Jun 17, 2026
Nov 1, 2023
N/A· v4
7.5 HIGH· v3
N/A· v2
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 at...Show more
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.Show less
1Squid Cache
1Squid
Jun 17, 2026
Dec 25, 2022
N/A· v4
8.6 HIGH· v3
N/A· v2
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 s...Show more
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.Show less
1Squid Cache
1Squid
Jun 17, 2026
Dec 25, 2022
N/A· v4
6.5 MEDIUM· v3
N/A· v2
An issue was discovered in Squid 4.9 through 4.17 and 5.0.6 through 5.6. Due to inconsistent handling of internal URIs, there can be Exposure of Sensitive Information about clients using the proxy via an HTTPS request to...Show more
An issue was discovered in Squid 4.9 through 4.17 and 5.0.6 through 5.6. Due to inconsistent handling of internal URIs, there can be Exposure of Sensitive Information about clients using the proxy via an HTTPS request to an internal cache manager URL. This is fixed in 5.7.Show less
2Debian
Squid Cache
2Debian Linux
Squid
Jun 17, 2026
Jul 17, 2022
N/A· v4
6.5 MEDIUM· v3
N/A· v2
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.
2Fedoraproject
Squid Cache
2Fedora
Squid
Jun 17, 2026
Oct 18, 2021
N/A· v4
7.5 HIGH· v3
5.0 MEDIUM· v2
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 t...Show more
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.Show less
3Fedoraproject
NetappSquid Cache
3Cloud Manager
FedoraSquid
Jun 17, 2026
Jun 8, 2021
N/A· v4
6.5 MEDIUM· v3
4.0 MEDIUM· v2
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...Show more
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.Show less
3Debian
FedoraprojectSquid Cache
3Debian Linux
FedoraSquid
Jun 17, 2026
May 28, 2021
N/A· v4
6.5 MEDIUM· v3
4.0 MEDIUM· v2
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...Show more
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.Show less
4Debian
FedoraprojectNetapp+1 more
4Cloud Manager
Debian LinuxFedora+1 more
Jun 17, 2026
May 27, 2021
N/A· v4
6.5 MEDIUM· v3
4.0 MEDIUM· v2
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 reques...Show more
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.Show less
4Debian
FedoraprojectNetapp+1 more
4Cloud Manager
Debian LinuxFedora+1 more
Jun 17, 2026
May 27, 2021
N/A· v4
6.5 MEDIUM· v3
4.0 MEDIUM· v2
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.
3Debian
FedoraprojectSquid Cache
3Debian Linux
FedoraSquid
Jun 17, 2026
May 27, 2021
N/A· v4
6.5 MEDIUM· v3
4.3 MEDIUM· v2
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 networ...Show more
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.Show less
3Debian
FedoraprojectSquid Cache
3Debian Linux
FedoraSquid
Jun 17, 2026
May 27, 2021
N/A· v4
4.9 MEDIUM· v3
4.0 MEDIUM· v2
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 le...Show more
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.Show less
4Debian
FedoraprojectNetapp+1 more
4Cloud Manager
Debian LinuxFedora+1 more
Jun 17, 2026
May 27, 2021
N/A· v4
7.5 HIGH· v3
5.0 MEDIUM· v2
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....Show more
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.Show less
4Debian
FedoraprojectNetapp+1 more
4Cloud Manager
Debian LinuxFedora+1 more
Jun 17, 2026
Mar 19, 2021
N/A· v4
8.6 HIGH· v3
5.0 MEDIUM· v2
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...Show more
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 uri_whitespace configuration settings.Show less
3Debian
FedoraprojectSquid Cache
3Debian Linux
FedoraSquid
Jun 17, 2026
Mar 9, 2021
N/A· v4
5.3 MEDIUM· v3
4.3 MEDIUM· v2
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 a...Show more
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.Show less
5Canonical
DebianFedoraproject+2 more
5Debian Linux
FedoraLeap+2 more
Jun 17, 2026
Sep 2, 2020
N/A· v4
6.5 MEDIUM· v3
4.0 MEDIUM· v2
An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Splitting attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows a...Show more
An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Splitting attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows any client, including browser scripts, to bypass local security and poison the browser cache and any downstream caches with content from an arbitrary source. Squid uses a string search instead of parsing the Transfer-Encoding header to find chunked encoding. This allows an attacker to hide a second request inside Transfer-Encoding: it is interpreted by Squid as chunked and split out into a second request delivered upstream. Squid will then deliver two distinct responses to the client, corrupting any downstream caches.Show less
5Canonical
DebianFedoraproject+2 more
5Debian Linux
FedoraLeap+2 more
Jun 17, 2026
Sep 2, 2020
N/A· v4
6.5 MEDIUM· v3
3.5 LOW· v2
An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Smuggling attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows a...Show more
An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Smuggling attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows any client, including browser scripts, to bypass local security and poison the proxy cache and any downstream caches with content from an arbitrary source. When configured for relaxed header parsing (the default), Squid relays headers containing whitespace characters to upstream servers. When this occurs as a prefix to a Content-Length header, the frame length specified will be ignored by Squid (allowing for a conflicting length to be used from another Content-Length header) but relayed upstream.Show less
5Canonical
DebianFedoraproject+2 more
5Debian Linux
FedoraLeap+2 more
Jun 17, 2026
Aug 24, 2020
N/A· v4
7.5 HIGH· v3
7.1 HIGH· v2
Squid before 4.13 and 5.x before 5.0.4 allows a trusted peer to perform Denial of Service by consuming all available CPU cycles during handling of a crafted Cache Digest response message. This only occurs when cache_peer...Show more
Squid before 4.13 and 5.x before 5.0.4 allows a trusted peer to perform Denial of Service by consuming all available CPU cycles during handling of a crafted Cache Digest response message. This only occurs when cache_peer is used with the cache digests feature. The problem exists because peerDigestHandleReply() livelocking in peer_digest.cc mishandles EOF.Show less
1Squid Cache
1Squid
Jun 17, 2026
Jun 30, 2020
N/A· v4
6.5 MEDIUM· v3
4.0 MEDIUM· v2
An issue was discovered in Squid 5.x before 5.0.3. Due to an Incorrect Synchronization, a Denial of Service can occur when processing objects in an SMP cache because of an Ipc::Mem::PageStack::pop ABA problem during acce...Show more
An issue was discovered in Squid 5.x before 5.0.3. Due to an Incorrect Synchronization, a Denial of Service can occur when processing objects in an SMP cache because of an Ipc::Mem::PageStack::pop ABA problem during access to the memory page/slot management list.Show less