Apache HTTP Server

In Apache HTTP Server versions 2.4.0 to 2.4.23, mod_session_crypto was encrypting its data/cookie using the configured ciphers with possibly either CBC or ECB modes of operation (AES256-CBC by default), hence no selectable or builtin authenticated encryption. This made it vulnerable to padding oracle attacks, particularly with CBC.

Request splitting via HTTP/2 method injection and mod_proxy

Stack-based buffer overflow in the ssl_util_uuencode_binary function in ssl_util.c for Apache mod_ssl, when mod_ssl is configured to trust the issuing CA, may allow remote attackers to execute arbitrary code via a client certificate with a long subject DN.

Apache HTTP Server: mod_rewrite proxy handler substitution

Apache HTTP Server: mod_http2 denial of service

Buffer overflow in htdigest in Apache 2.0.52 may allow attackers to execute arbitrary code via a long realm argument. NOTE: since htdigest is normally only locally accessible and not setuid or setgid, there are few attack vectors which would lead to an escalation of privileges, unless htdigest is executed from a CGI program. Therefore this may not be a vulnerability.

List of arbitrary files on Web host via nph-test-cgi script.

ScriptAlias directory in NCSA and Apache httpd allowed attackers to read CGI programs.

null pointer dereference in h2 fuzzing

PHP, when installed on Windows with Apache and ScriptAlias for /php/ set to c:/php/, allows remote attackers to read arbitrary files and possibly execute arbitrary programs via an HTTP request for php.exe with a filename in the query string.

Buffer overflows in the ApacheBench benchmark support program (ab.c) in Apache before 1.3.27, and Apache 2.x before 2.0.43, allow a malicious web server to cause a denial of service and possibly execute arbitrary code via a long response.

mod_proxy_ajp: Possible request smuggling

In Apache HTTP Server versions 2.4.0 to 2.4.23, malicious input to mod_auth_digest can cause the server to crash, and each instance continues to crash even for subsequently valid requests.

In Apache HTTP Server 2.4 release 2.4.37 and prior, mod_session checks the session expiry time before decoding the session. This causes session expiry time to be ignored for mod_session_cookie sessions since the expiry time is loaded when the session is decoded.

The Apache HTTP Server 2.4.18 through 2.4.20, when mod_http2 and mod_ssl are enabled, does not properly recognize the "SSLVerifyClient require" directive for HTTP/2 request authorization, which allows remote attackers to bypass intended access restrictions by leveraging the ability to send multiple requests over a single connection and aborting a renegotiation.

Apache before 2.0.44, when running on unpatched Windows 9x and Me operating systems, allows remote attackers to cause a denial of service or execute arbitrary code via an HTTP request containing MS-DOS device names.

In Apache HTTP Server 2.4 release 2.4.38 and prior, a race condition in mod_auth_digest when running in a threaded server could allow a user with valid credentials to authenticate using another username, bypassing configured access control restrictions.

mod_cgi in Apache 2.0.39 and 2.0.40 allows local users and possibly remote attackers to cause a denial of service (hang and memory consumption) by causing a CGI script to send a large amount of data to stderr, which results in a read/write deadlock between httpd and the CGI script.

DoS for HTTP/2 connections by crafted requests

In Apache httpd 2.0.23 to 2.0.65, 2.2.0 to 2.2.34, and 2.4.0 to 2.4.29, mod_authnz_ldap, if configured with AuthLDAPCharsetConfig, uses the Accept-Language header value to lookup the right charset encoding when verifying the user's credentials. If the header value is not present in the charset conversion table, a fallback mechanism is used to truncate it to a two characters value to allow a quick retry (for example, 'en-US' is truncated to 'en'). A header value of less than two characters forces an out of bound write of one NUL byte to a memory location that is not part of the string. In the worst case, quite unlikely, the process would crash which could be used as a Denial of Service attack. In the more likely case, this memory is already reserved for future use and the issue has no effect at all.

HTTP/2 (2.4.20 through 2.4.39) very early pushes, for example configured with "H2PushResource", could lead to an overwrite of memory in the pushing request's pool, leading to crashes. The memory copied is that of the configured push link header values, not data supplied by the client.

mod_session_dbd.c in the mod_session_dbd module in the Apache HTTP Server before 2.4.5 proceeds with save operations for a session without considering the dirty flag and the requirement for a new session ID, which has unspecified impact and remote attack vectors.

The Solaris pollset feature in the Event Port backend in poll/unix/port.c in the Apache Portable Runtime (APR) library before 1.3.9, as used in the Apache HTTP Server before 2.2.14 and other products, does not properly handle errors, which allows remote attackers to cause a denial of service (daemon hang) via unspecified HTTP requests, related to the prefork and event MPMs.

The mod_ssl module in Apache 2.0.35 through 2.0.52, when using the "SSLCipherSuite" directive in directory or location context, allows remote clients to bypass intended restrictions by using any cipher suite that is allowed by the virtual host configuration.

Apache HTTP Server, in all releases prior to 2.2.32 and 2.4.25, was liberal in the whitespace accepted from requests and sent in response lines and headers. Accepting these different behaviors represented a security concern when httpd participates in any chain of proxies or interacts with back-end application servers, either through mod_proxy or using conventional CGI mechanisms, and may result in request smuggling, response splitting and cache pollution.

Heap-based buffer overflow in the fcgid_header_bucket_read function in fcgid_bucket.c in the mod_fcgid module before 2.3.9 for the Apache HTTP Server allows remote attackers to have an unspecified impact via unknown vectors.

Apache 1.4.x before 1.3.30, and 2.0.x before 2.0.49, when using multiple listening sockets on certain platforms, allows remote attackers to cause a denial of service (blocked new connections) via a "short-lived connection on a rarely-accessed listening socket."

mod_access in Apache 1.3 before 1.3.30, when running big-endian 64-bit platforms, does not properly parse Allow/Deny rules using IP addresses without a netmask, which could allow remote attackers to bypass intended access restrictions.

In Apache HTTP Server 2.4 releases 2.4.37 and 2.4.38, a bug in mod_ssl when using per-location client certificate verification with TLSv1.3 allowed a client to bypass configured access control restrictions.

When under stress, closing many connections, the HTTP/2 handling code in Apache httpd 2.4.26 would sometimes access memory after it has been freed, resulting in potentially erratic behaviour.

The default installation of Apache before 1.3.19 on Mandrake Linux 7.1 through 8.0 and Linux Corporate Server 1.0.1 allows remote attackers to list the directory index of arbitrary web directories.

Unknown vulnerability in Apache 2.0.51 prevents "the merging of the Satisfy directive," which could allow attackers to obtain access to restricted resources contrary to the specified authentication configuration.

mod_digest_apple for Apache 1.3.31 and 1.3.32 on Mac OS X Server does not properly verify the nonce of a client response, which allows remote attackers to replay credentials.

Denial of service in mod_lua r:parsebody

Directory traversal vulnerability in Ragnarok Online Control Panel 4.3.4a, when the Apache HTTP Server is used, allows remote attackers to bypass authentication via directory traversal sequences in a URI that ends with the name of a publicly available page, as demonstrated by a "/...../" sequence and an account_manage.php/login.php final component for reaching the protected account_manage.php page.

SQL injection vulnerability in mysql/mysql-auth.pl in the mod_authnz_external module 3.2.5 and earlier for the Apache HTTP Server allows remote attackers to execute arbitrary SQL commands via the user field.

mod_digest for Apache before 1.3.31 does not properly verify the nonce of a client response by using a AuthNonce secret.

Information Disclosure in mod_lua with websockets

Apache HTTP Server: HTTP/2 DoS by Memory Increase

Cross-site scripting vulnerability in auction.pl of MakeBid Auction Deluxe 3.30 allows remote attackers to obtain information from other users via the form fields (1) TITLE, (2) DESCTIT, (3) DESC, (4) searchstring, (5) ALIAS, (6) EMAIL, (7) ADDRESS1, (8) ADDRESS2, (9) ADDRESS3, (10) PHONE1, (11) PHONE2, (12) PHONE3, or (13) PHONE4.