This page lists publicly disclosed CVE vulnerabilities affecting squid-cache squid (linked via NVD CPE). Each row includes severity scores, summaries, and publication dates to help identify and analyze security issues.
| CVE | Summary | Source | Max CVSS | EPSS % | Published | Updated |
|---|---|---|---|---|---|---|
| CVE-2023-46847 | 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. | [email protected] | 8.6 | 85.83% | 2023-11-03 | 2026-06-17 |
| CVE-2023-46846 | 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. | [email protected] | 9.3 | 5.25% | 2023-11-03 | 2026-06-17 |
| CVE-2023-46724 | 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 b | [email protected] | 8.6 | 4.01% | 2023-11-01 | 2026-06-17 |
| CVE-2022-41318 | 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. | [email protected] | 8.6 | 2.84% | 2022-12-25 | 2026-06-17 |
| CVE-2022-41317 | 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. | [email protected] | 6.5 | 1.69% | 2022-12-25 | 2026-06-17 |
| CVE-2021-46784 | 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. | [email protected] | 6.5 | 4.51% | 2022-07-17 | 2026-06-17 |
| CVE-2021-41611 | 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. | [email protected] | 7.5 | 2.85% | 2021-10-18 | 2026-06-17 |
| CVE-2021-31807 | 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. | [email protected] | 6.5 | 15.97% | 2021-06-08 | 2026-06-16 |
| CVE-2021-33620 | 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. | [email protected] | 6.5 | 79.58% | 2021-05-28 | 2026-06-16 |
| CVE-2021-31808 | 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. | [email protected] | 6.5 | 5.49% | 2021-05-27 | 2026-06-16 |
| CVE-2021-31806 | 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. | [email protected] | 6.5 | 95.78% | 2021-05-27 | 2026-06-16 |
| CVE-2021-28662 | 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. | [email protected] | 6.5 | 71.87% | 2021-05-27 | 2026-06-16 |
| CVE-2021-28652 | 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. | [email protected] | 4.9 | 4.34% | 2021-05-27 | 2026-06-16 |
| CVE-2021-28651 | 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. | [email protected] | 7.5 | 7.45% | 2021-05-27 | 2026-06-16 |
| CVE-2020-25097 | 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. | [email protected] | 8.6 | 8.16% | 2021-03-19 | 2026-06-16 |
| CVE-2021-28116 | 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. | [email protected] | 3.7 | 13.00% | 2021-03-09 | 2026-06-16 |
| CVE-2020-15811 | 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 attacke | [email protected] | 6.5 | 4.23% | 2020-09-02 | 2026-06-16 |
| CVE-2020-15810 | 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 s | [email protected] | 6.5 | 2.54% | 2020-09-02 | 2026-06-16 |
| CVE-2020-24606 | 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. | [email protected] | 8.6 | 5.16% | 2020-08-24 | 2026-06-16 |
| CVE-2020-14059 | 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. | [email protected] | 6.5 | 4.41% | 2020-06-30 | 2026-06-16 |