CVE-2020-11945

Squid vulnerability CVE-2020-11945 is confirmed in various advisories for Squid prior to 5.0.2, where a remote attacker can replay a sniffed Digest Authentication nonce due to overflow of the nonce reference counter, potentially enabling remote code execution if pooled token credentials are freed...

CVE-2019-12525

CVE-2019-12525 affects Squid (3.3.9–3.5.28 and 4.x–4.7). When Digest authentication is used, Proxy-Authorization parsing may treat a single quote as valid and memcpy with length−1, causing memory corruption. Connected advisories confirm the issue and reference updates to Squid versions; however e...

CVE-2019-12526

CVE-2019-12526 affects Squid prior to 4.9, where URN response handling can overflow the heap with attacker-controlled data when processing URN responses from a remote server. The connected advisories confirm that a fix is available in newer upstream versions (e.g., 4.10+ as reflected in ALT Linux...

CVE-2020-15049

CVE-2020-15049 affects Squid up to 4.12 and 5.x up to 5.0.3. It enables a Request Smuggling and Poisoning attack against the HTTP cache by sending Content-Length values with a prefix like +, - or uncommon whitespace. Affected component: http/ContentLengthInterpreter.cc. Impact: potential cache po...

CVE-2019-12519

CVE-2019-12519 in Squid (up to 4.7) originates from ESI handling: ESIExpression::Evaluate uses a fixed stack buffer and does not check for overflow when adding a new member, causing a stack/heap overflow under certain expressions and potentially impacting confidentiality, integrity, and availabil...

CVE-2019-12523

CVE-2019-12523 affects Squid prior to 4.9, where handling a URN request transforms it into an HTTP request that bypasses the standard incoming HTTP access checks. This allows an attacker to access restricted HTTP servers (e.g., localhost) by bypassing ACLs via the URN path, with potential exposur...

CVE-2019-18678

CVE-2019-18678 affects Squid 3.x and 4.x up to 4.8. It arises from a request header with whitespace between a header name and a colon, enabling an attacker to smuggle HTTP requests through frontend software to a Squid instance. The resulting Response messages corrupt caches between the client and...

CVE-2019-18679

The CVE-2019-18679 issue affects Squid 2.x–4.x (through 4.8) and arises from incorrect data management during HTTP Digest Authentication, where nonce tokens contain the raw pointer byte value from heap memory. This information disclosure reduces ASLR effectiveness and could assist attackers targe...

CVE-2019-12529

CVE-2019-12529 affects Squid 2.x–4.x (up to 4.7) where Basic Authentication parsing decodes Proxy-Authorization using uudecode. The decoder does not validate that the calculated decode length fits the input buffer, causing adjacent memory to be decoded and enabling a potential DoS via out-of-boun...

CVE-2021-46784

The CVE-2021-46784 issue affects Squid 3.x–3.5.28, 4.x–4.17, and 5.x prior to 5.6, caused by improper buffer management that can lead to a Denial of Service when processing long Gopher server responses. Affected releases are vulnerable to DoS; remediation is to update to a fixed version (5.6 or l...

CVE-2019-18676

CVE-2019-18676 affects Squid 3.x and 4.x up to 4.8, where incorrect input validation enables a heap-based buffer overflow that can cause a Denial of Service to all clients using the proxy. The connected advisories describe the issue scope and related CVEs in the same Squid codebase (URn/URI proce...

CVE-2019-18677

CVE-2019-18677 affects Squid 3.x and 4.x up to 4.8 where the append_domain setting can cause improper message processing, leading to traffic being redirected to origins that should not be delivered to. This is confirmed in multiple advisories (e.g., ALAS2-2023-2318) listing CVE-2019-18677 as a se...

CVE-2019-12521

CVE-2019-12521 is a Squid vulnerability where, while parsing ESI, the ESIContext buffer used to hold ESIElements is overflowed due to an off-by-one bug in addStackElement. The overflow is within the same structure and causes a crash during processing (not adjacent memory corruption). Affected: Sq...

CVE-2018-1000024

The CVE-2018-1000024 vulnerability affects Squid HTTP Caching Proxy (versions 3.0–3.5.27 and 4.0–4.0.22). It is caused by Incorrect Pointer Handling in ESI Response Processing, enabling a Denial of Service when a remote server delivers an HTTP response payload with valid but unusual ESI syntax. I...

CVE-2020-14058

CVE-2020-14058 affects Squid before 4.12 and 5.x before 5.0.3. The DoS condition occurs when opening a TLS connection to an attacker-controlled HTTPS server due to using a potentially dangerous function and mapping unrecognized error values to NULL, with later code expecting valid error strings. ...

CVE-2019-12854

CVE-2019-12854 affects Squid up to 4.7, where incorrect string termination in cachemgr.cgi can cause access to unallocated memory and DoS for clients. Public advisories document this as a Denial of Service vector and list Squid 4.0–4.7 as affected; remediation seen in later vendor advisories/upda...