CVE-2020-11945

An issue was discovered in Squid before 5.0.2. A remote attacker can replay a sniffed Digest Authentication nonce to gain access to resources that are otherwise forbidden. This occurs because the attacker can overflow the nonce reference counter (a short integer). Remote code execution may occur if the pooled token credentials are freed (instead of replayed as valid credentials).

Squid is a high-performance proxy caching server. It handles all requests in a single, non-blocking, I/O-driven process and keeps meta data and implements negative caching of failed requests.

Security Fix(es):

An issue was discovered in Squid before 4.12 and 5.x before 5.0.3. Due to use of a potentially dangerous function, Squid and the default certificate validation helper are vulnerable to a Denial of Service when opening a TLS connection to an attacker-controlled server for HTTPS. This occurs because unrecognized error values are mapped to NULL, but later code expects that each error value is mapped to a valid error string.(CVE-2020-14058)

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.(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 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.(CVE-2020-15811)

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.(CVE-2020-24606)

An issue was discovered in Squid before 5.0.2. A remote attacker can replay a sniffed Digest Authentication nonce to gain access to resources that are otherwise forbidden. This occurs because the attacker can overflow the nonce reference counter (a short integer). Remote code execution may occur if the pooled token credentials are freed (instead of replayed as valid credentials).(CVE-2020-11945)

An issue was discovered in http/ContentLengthInterpreter.cc in Squid before 4.12 and 5.x before 5.0.3. A Request Smuggling and Poisoning attack can succeed against the HTTP cache. The client sends an HTTP request with a Content-Length header containing "+\ "-" or an uncommon shell whitespace character prefix to the length field-value.(CVE-2020-15049)

Squid is a high-performance proxy caching server for web clients, supporting FTP, Gopher, and HTTP data objects.

Security Fix(es):

• squid: improper check for new member in ESIExpression::Evaluate allows for stack buffer overflow (CVE-2019-12519)

• squid: improper access restriction upon Digest Authentication nonce replay could lead to remote code execution (CVE-2020-11945)

• squid: parsing of header Proxy-Authentication leads to memory corruption (CVE-2019-12525)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

An issue was discovered in Squid before 5.0.2. A remote attacker can replay a sniffed Digest Authentication nonce to gain access to resources that are otherwise forbidden. This occurs because the attacker can overflow the nonce reference counter (a short integer). Remote code execution may occur if the pooled token credentials are freed (instead of replayed as valid credentials).

Squid is a high-performance proxy caching server for web clients, supporting FTP, Gopher, and HTTP data objects.

Security Fix(es):

• squid: improper check for new member in ESIExpression::Evaluate allows for stack buffer overflow (CVE-2019-12519)

• squid: improper access restriction upon Digest Authentication nonce replay could lead to remote code execution (CVE-2020-11945)

• squid: parsing of header Proxy-Authentication leads to memory corruption (CVE-2019-12525)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

• CVE-2020-15049: fix incorrect validation of Content-Length field leading to Http smuggling and Poisoning attack
• CVE-2020-14058: fix handling of unknown SSL errors which resulted in denial of service
• CVE-2020-25097: fix improper input validation allowing HTTP smuggling from trusted client
• CVE-2020-11945: fix nonce reference counter overflow allowing replay attack
• CVE-2020-24606: fix handle of EOF in peerDigestHandleReply() leading to Denial of service
• CVE-2020-8517: fix incorrect input validation allowing writing outside of buffer and leading to denial of service
• CVE-2020-8449: fix improper HTTP request validation allowing access to resources which are prohibited by security filters
• CVE-2020-8450: fix incorrect buffer managment leading to buffer overflow
• CVE-2021-28651: fix memory leak leading to denial of service

• CVE-2020-15049: fix incorrect validation of Content-Length field leading to Http smuggling and Poisoning attack
• CVE-2020-14058: fix handling of unknown SSL errors which resulted in denial of service
• CVE-2020-25097: fix improper input validation allowing HTTP smuggling from trusted client
• CVE-2020-11945: fix nonce reference counter overflow allowing replay attack
• CVE-2020-24606: fix handle of EOF in peerDigestHandleReply() leading to Denial of service
• CVE-2020-8517: fix incorrect input validation allowing writing outside of buffer and leading to denial of service
• CVE-2020-8449: fix improper HTTP request validation allowing access to resources which are prohibited by security filters
• CVE-2020-8450: fix incorrect buffer managment leading to buffer overflow
• CVE-2021-28651: fix memory leak leading to denial of service

Updated squid packages fix security vulnerability:

Due to an integer overflow bug Squid is vulnerable to credential replay and remote code execution attacks against HTTP Digest Authentication tokens. When memory pooling is used this problem allows a remote client to replay a sniffed Digest Authentication nonce to gain access to resources that are otherwise forbidden. When memory pooling is disabled this problem allows a remote client to perform remote code execution through the free'd nonce credentials (CVE-2020-11945).

This update for squid to version 4.11 fixes the following issues:

• CVE-2020-11945: Fixed a potential remote code execution vulnerability when using HTTP Digest Authentication (bsc#1170313).
• CVE-2019-12519, CVE-2019-12521: Fixed incorrect buffer handling that can result in cache poisoning, remote execution, and denial of service attacks when processing ESI responses (bsc#1169659).
• CVE-2020-8517: Fixed a possible denial of service caused by incorrect buffer management ext_lm_group_acl when processing NTLM Authentication credentials (bsc#1162691).
• CVE-2019-12528: Fixed possible information disclosure when translating FTP server listings into HTTP responses (bsc#1162689).
• CVE-2019-18860: Fixed handling of invalid domain names in cachemgr.cgi (bsc#1167373).

This update was imported from the SUSE:SLE-15:Update update project.

These are all security issues fixed in the squid-4.16-1.5 package on the GA media of openSUSE Tumbleweed.

This update for squid to version 4.11 fixes the following issues:

• CVE-2020-11945: Fixed a potential remote code execution vulnerability when using HTTP Digest Authentication (bsc#1170313).
• CVE-2019-12519, CVE-2019-12521: Fixed incorrect buffer handling that can result in cache poisoning, remote execution, and denial of service attacks when processing ESI responses (bsc#1169659).
• CVE-2020-8517: Fixed a possible denial of service caused by incorrect buffer management ext_lm_group_acl when processing NTLM Authentication credentials (bsc#1162691).
• CVE-2019-12528: Fixed possible information disclosure when translating FTP server listings into HTTP responses (bsc#1162689).
• CVE-2019-18860: Fixed handling of invalid domain names in cachemgr.cgi (bsc#1167373).

This update for squid to version 4.11 fixes the following issues:

• CVE-2020-11945: Fixed a potential remote code execution vulnerability when using HTTP Digest Authentication (bsc#1170313).
• CVE-2019-12519, CVE-2019-12521: Fixed incorrect buffer handling that can result in cache poisoning, remote execution, and denial of service attacks when processing ESI responses (bsc#1169659).
• CVE-2020-8517: Fixed a possible denial of service caused by incorrect buffer management ext_lm_group_acl when processing NTLM Authentication credentials (bsc#1162691).
• CVE-2019-12528: Fixed possible information disclosure when translating FTP server listings into HTTP responses (bsc#1162689).
• CVE-2019-18860: Fixed handling of invalid domain names in cachemgr.cgi (bsc#1167373).

This update for squid fixes the following issues:

• CVE-2019-12519, CVE-2019-12521: fixes incorrect buffer handling that can result in cache poisoning, remote execution, and denial of service attacks when processing ESI responses (bsc#1169659).
• CVE-2020-11945: fixes a potential remote execution vulnerability when using HTTP Digest Authentication (bsc#1170313).
• CVE-2019-12520, CVE-2019-12524: fixes a potential ACL bypass, cache-bypass and cross-site scripting attack when processing invalid HTTP Request messages (bsc#1170423).

This update for squid3 fixes the following issues:

• Fixed a Cache Poisoning and Request Smuggling attack (CVE-2020-15049, bsc#1173455)

• Fixed incorrect buffer handling that can result in cache poisoning, remote execution, and denial of service attacks when processing ESI responses (CVE-2019-12519, CVE-2019-12521, bsc#1169659)

• Fixed handling of hostname in cachemgr.cgi (CVE-2019-18860, bsc#1167373)

• Fixed a potential remote execution vulnerability when using HTTP Digest Authentication (CVE-2020-11945, bsc#1170313)

• Fixed a potential ACL bypass, cache-bypass and cross-site scripting attack when processing invalid HTTP Request messages (CVE-2019-12520, CVE-2019-12524, bsc#1170423)

• Fixed a potential denial of service when processing TLS certificates during HTTPS connections (CVE-2020-14059, bsc#1173304)

• Fixed a potential denial of service associated with incorrect buffer management of HTTP Basic Authentication credentials (bsc#1141329, CVE-2019-12529)

• Fixed an incorrect buffer management resulting in vulnerability to a denial of service during processing of HTTP Digest Authentication credentials (bsc#1141332, CVE-2019-12525)

• Fix XSS via user_name or auth parameter in cachemgr.cgi (bsc#1140738, CVE-2019-13345)

• Fixed a potential code execution vulnerability (CVE-2019-12526, bsc#1156326)

• Fixed HTTP Request Splitting in HTTP message processing and information disclosure in HTTP Digest Authentication (CVE-2019-18678, CVE-2019-18679, bsc#1156323, bsc#1156324)

• Fixed a security issue allowing a remote client ability to cause use a buffer overflow when squid is acting as reverse-proxy. (CVE-2020-8449, CVE-2020-8450, bsc#1162687)

• Fixed a security issue allowing for information disclosure in FTP gateway (CVE-2019-12528, bsc#1162689)

• Fixed a security issue in ext_lm_group_acl when processing NTLM Authentication credentials. (CVE-2020-8517, bsc#1162691)

• Fixed Cross-Site Request Forgery in HTTP Request processing (CVE-2019-18677, bsc#1156328)

• Disable urn parsing and parsing of unknown schemes (bsc#1156329, CVE-2019-12523, CVE-2019-18676)

Jeriko One discovered that Squid incorrectly handled certain Edge Side Includes (ESI) responses. A malicious remote server could cause Squid to crash, possibly poison the cache, or possibly execute arbitrary code. (CVE-2019-12519, CVE-2019-12521)

It was discovered that Squid incorrectly handled the hostname parameter to cachemgr.cgi when certain browsers are used. A remote attacker could possibly use this issue to inject HTML or invalid characters in the hostname parameter. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 19.10. (CVE-2019-18860)

Clément Berthaux and Florian Guilbert discovered that Squid incorrectly handled Digest Authentication nonce values. A remote attacker could use this issue to replay nonce values, or possibly execute arbitrary code. (CVE-2020-11945)