SquidCVEs & Vulnerabilities

Squid, when transparent interception mode is enabled, uses the HTTP Host header to determine the remote endpoint, which allows remote attackers to bypass access controls for Flash, Java, Silverlight, and probably other technologies, and possibly communicate with restricted intranet sites, via a crafted web page that causes a client to send HTTP requests with a modified Host header.

Squid 2.7 to 2.7.STABLE5, 3.0 to 3.0.STABLE12, and 3.1 to 3.1.0.4 allows remote attackers to cause a denial of service via an HTTP request with an invalid version number, which triggers a reachable assertion in (1) HttpMsg.c and (2) HttpStatusLine.c.

The arrayShrink function (lib/Array.c) in Squid 2.6.STABLE17 allows attackers to cause a denial of service (process exit) via unknown vectors that cause an array to shrink to 0 entries, which triggers an assert error. NOTE: this issue is due to an incorrect fix for CVE-2007-6239.

The "cache update reply processing" functionality in Squid 2.x before 2.6.STABLE17 and Squid 3.0 allows remote attackers to cause a denial of service (crash) via unknown vectors related to HTTP headers and an Array memory leak during requests for cached objects.

The clientProcessRequest() function in src/client_side.c in Squid 2.6 before 2.6.STABLE12 allows remote attackers to cause a denial of service (daemon crash) via crafted TRACE requests that trigger an assertion error.

The aclMatchExternal function in Squid before 2.6.STABLE7 allows remote attackers to cause a denial of service (crash) by causing an external_acl queue overload, which triggers an infinite loop.

squid/src/ftp.c in Squid before 2.6.STABLE7 allows remote FTP servers to cause a denial of service (core dump) via crafted FTP directory listing responses, possibly related to the (1) ftpListingFinish and (2) ftpHtmlifyListEntry functions.

Unspecified vulnerability in Squid on SUSE Linux 9.0 allows remote attackers to cause a denial of service (crash) via HTTPs (SSL).

The rfc1738_do_escape function in ftp.c for Squid 2.5 STABLE11 and earlier allows remote FTP servers to cause a denial of service (segmentation fault) via certain "odd" responses.

Squid 2.5.STABLE10 and earlier, while performing NTLM authentication, does not properly handle certain request sequences, which allows attackers to cause a denial of service (daemon restart).

store.c in Squid 2.5.STABLE10 and earlier allows remote attackers to cause a denial of service (crash) via certain aborted requests that trigger an assert error related to STORE_PENDING.

The sslConnectTimeout function in ssl.c for Squid 2.5.STABLE10 and earlier allows remote attackers to cause a denial of service (segmentation fault) via certain crafted requests.

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.

Squid 2.5 STABLE9 and earlier, when the DNS client port is unfiltered and the environment does not prevent IP spoofing, allows remote attackers to spoof DNS lookups.

Squid 2.5.STABLE9 and earlier does not trigger a fatal error when it identifies missing or invalid ACLs in the http_access configuration, which could lead to less restrictive ACLs than intended by the administrator.

squid_ldap_auth in Squid 2.5 and earlier allows remote authenticated users to bypass username-based Access Control Lists (ACLs) via a username with a space at the beginning or end, which is ignored by the LDAP server.

Squid 2.5, when processing the configuration file, parses empty Access Control Lists (ACLs), including proxy_auth ACLs without defined auth schemes, in a way that effectively removes arguments, which could allow remote attackers to bypass intended ACLs if the administrator ignores the parser warnings.

The httpProcessReplyHeader function in http.c for Squid 2.5-STABLE7 and earlier does not properly set the debug context when it is handling "oversized" HTTP reply headers, which might allow remote attackers to poison the cache or bypass access controls based on header size.

Squid 2.5.STABLE8 and earlier allows remote attackers to cause a denial of service (crash) via certain DNS responses regarding (1) Fully Qualified Domain Names (FQDN) in fqdncache.c or (2) IP addresses in ipcache.c, which trigger an assertion failure.

Squid 2.5.STABLE7 and earlier allows remote attackers to cause a denial of service (segmentation fault) by aborting the connection during a (1) PUT or (2) POST request, which causes Squid to access previously freed memory.

Race condition in Squid 2.5.STABLE7 to 2.5.STABLE9, when using the Netscape Set-Cookie recommendations for handling cookies in caches, may cause Set-Cookie headers to be sent to other users, which allows attackers to steal the related cookies.

Squid 2.5 up to 2.5.STABLE7 allows remote attackers to poison the cache or conduct certain attacks via headers that do not follow the HTTP specification, including (1) multiple Content-Length headers, (2) carriage return (CR) characters that are not part of a CRLF pair, and (3) header names containing whitespace characters.

Squid 2.5 up to 2.5.STABLE7 allows remote attackers to poison the cache via an HTTP response splitting attack.

The asn_parse_header function (asn1.c) in the SNMP module for Squid Web Proxy Cache before 2.4.STABLE7 allows remote attackers to cause a denial of service (server restart) via certain SNMP packets with negative length fields that trigger a memory allocation error.

Memory leak in the NTLM fakeauth_auth helper for Squid 2.5.STABLE7 and earlier allows remote attackers to cause a denial of service (memory consumption).

Buffer overflow in the gopherToHTML function in the Gopher reply parser for Squid 2.5.STABLE7 and earlier allows remote malicious Gopher servers to cause a denial of service (crash) via crafted responses.

The WCCP message parsing code in Squid 2.5.STABLE7 and earlier allows remote attackers to cause a denial of service (crash) via malformed WCCP messages with source addresses that are spoofed to reference Squid's home router and invalid WCCP_I_SEE_YOU cache numbers.

The NTLM component in Squid 2.5.STABLE7 and earlier allows remote attackers to cause a denial of service (crash) via a malformed NTLM type 3 message that triggers a NULL dereference.

The clientAbortBody function in client_side.c in Squid Web Proxy Cache before 2.6 STABLE6 allows remote attackers to cause a denial of service (segmentation fault) via unspecified vectors that trigger a null dereference. NOTE: in a followup advisory, a researcher claimed that the issue was a buffer overflow that was not fixed in STABLE6. However, the vendor's bug report clearly shows that the researcher later retracted this claim, because the tested product was actually STABLE5.

The (1) ntlm_fetch_string and (2) ntlm_get_string functions in Squid 2.5.6 and earlier, with NTLM authentication enabled, allow remote attackers to cause a denial of service (application crash) via an NTLMSSP packet that causes a negative value to be passed to memcpy.

The "%xx" URL decoding function in Squid 2.5STABLE4 and earlier allows remote attackers to bypass url_regex ACLs via a URL with a NULL ("%00") character, which causes Squid to use only a portion of the requested URL when comparing it against the access control lists.

Opera 6.0.3, when using Squid 2.4 for HTTPS proxying, does not properly handle when accepting a non-global certificate authority (CA) certificate from a site and establishing a subsequent HTTPS connection, which allows remote attackers to cause a denial of service (crash).

Buffer overflows in Squid before 2.4.STABLE6 allow remote attackers to cause a denial of service (crash) and possibly execute arbitrary code (1) via the MSNT auth helper (msnt_auth) when using denyusers or allowusers files, (2) via the gopher client, or (3) via the FTP server directory listing parser when HTML output is generated.

FTP proxy in Squid before 2.4.STABLE6 does not compare the IP addresses of control and data connections with the FTP server, which allows remote attackers to bypass firewall rules or spoof FTP server responses.

Vulnerability in Squid before 2.4.STABLE6 related to proxy authentication credentials may allow remote web sites to obtain the user's proxy login and password.

Heap-based buffer overflow in Squid before 2.4 STABLE4, and Squid 2.5 and 2.6 until March 12, 2002 distributions, allows remote attackers to cause a denial of service, and possibly execute arbitrary code, via compressed DNS responses.

Squid 2.4 STABLE3 and earlier does not properly disable HTCP, even when "htcp_port 0" is specified in squid.conf, which could allow remote attackers to bypass intended access restrictions.

Memory leak in SNMP in Squid 2.4 STABLE3 and earlier allows remote attackers to cause a denial of service.

Squid 2.4 STABLE3 and earlier allows remote attackers to cause a denial of service (core dump) and possibly execute arbitrary code with an ftp:// URL with a larger number of special characters, which exceed the buffer when Squid URL-escapes the characters.

Squid proxy server 2.4 and earlier allows remote attackers to cause a denial of service (crash) via a mkdir-only FTP PUT request.

Squid before 2.3STABLE5 in HTTP accelerator mode does not enable access control lists (ACLs) when the httpd_accel_host and http_accel_with_proxy off settings are used, which allows attackers to bypass the ACLs and conduct unauthorized activities such as port scanning.