Multiple stack-based buffer overflows in (1) modalias and (2) modrewrite for Apache before 1.3.29 allow attackers to create configuration files to cause a denial of service (crash) or execute arbitrary code via a regular expression with more than 9 captures.

Tomcat 4.0 through 4.1.12, using modjk 1.2.1 module on Apache 1.3 through 1.3.27, allows remote attackers to cause a denial of service (desynchronized communications) via an HTTP GET request with a Transfer-Encoding chunked field with invalid values.

Cross site scripting vulnerabilities in Apache 1.3.0 through 1.3.11 allow remote attackers to execute script as other web site visitors via (1) the printenv CGI (printenv.pl), which does not encode its output, (2) pages generated by the apsenderrorresponse function such as a default 404, which does not add an explicit charset, or (3) various messages that are generated by certain Apache modules or core code. NOTE: the printenv issue might still exist for web browsers that can render text/plain content types as HTML, such as Internet Explorer, but CVE regards this as a design limitation of those browsers, not Apache. The printenv.pl/acuparam vector, discloser on 20070724, is one such variant.

Apache WWW server 1.3.1 and earlier allows remote attackers to cause a denial of service (resource exhaustion) via a large number of MIME headers with the same name, aka the "sioux" vulnerability.

Integer overflow in the approxysendfb function in proxy/proxyutil.c in modproxy in the Apache HTTP Server before 1.3.42 on 64-bit platforms allows remote origin servers to cause a denial of service (daemon crash) or possibly execute arbitrary code via a large chunk size that triggers a heap-based buffer overflow.

SQL injection vulnerability in modaccounting.c in the modaccounting module 0.5 and earlier for Apache allows remote attackers to execute arbitrary SQL commands via a Host header.

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.

Buffer overflow in htdigest in Apache 1.3.26 and 1.3.27 may allow attackers to execute arbitrary code via a long user 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.

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.

Cross-site scripting (XSS) vulnerability in the default error page of Apache 2.0 before 2.0.43, and 1.3.x up to 1.3.26, when UseCanonicalName is "Off" and support for wildcard DNS is present, allows remote attackers to execute script as other web page visitors via the Host: header, a different vulnerability than CAN-2002-1157.

modaccess 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.

moddigestapple 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.

Buffer overflow in the gettag function in modinclude for Apache 1.3.x to 1.3.32 allows local users who can create SSI documents to execute arbitrary code as the apache user via SSI (XSSI) documents that trigger a length calculation error.

PHP 4.3.4 and earlier in Apache 1.x and 2.x (modphp) can leak global variables between virtual hosts that are handled by the same Apache child process but have different settings, which could allow remote attackers to obtain sensitive information.

Cross-site scripting (XSS) vulnerability in the modimap module of Apache httpd before 1.3.35-dev and Apache httpd 2.0.x before 2.0.56-dev allows remote attackers to inject arbitrary web script or HTML via the Referer when using image maps.

An Uncontrolled Resource Consumption vulnerability in multiple products may allow an attacker to cause web service portal denial of service (DoS) via handling special crafted HTTP requests/responses in pieces slowly. Slow HTTP attacks are denial-of-service (DoS) attacks in which the attacker sends HTTP requests in pieces slowly, one at a time to a Web server. If an HTTP request is not complete, or if the transfer rate is very low, the server keeps its resources busy waiting for the rest of the data. When the server’s concurrent connection pool reaches its maximum, this creates a DoS. Slow HTTP attacks are easy to execute because they require only minimal resources from the attacker.

Cross-site scripting (XSS) vulnerability in modstatus in the Apache HTTP Server 2.2.0 through 2.2.6, 2.0.35 through 2.0.61, and 1.3.2 through 1.3.39, when the server-status page is enabled, allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.

Additional problems were discovered in the httpd fix for CVE-2011-3368 - a reverse proxy bypass flaw - tracked via bug #740045. Upstream mailing list post identifies following request forms, which are not handled correctly:

GET @localhost::8880 HTTP/1.0\r\n\r\n GET qualys:@qqq.qq.qualys.com HTTP/1.0\r\n\r\n

Reference: http://thread.gmane.org/gmane.comp.apache.devel/46440

RMDG partner and independent security consultancy, "Context Information Security" has made CPNI Response aware of a security vulnerability which could potentially allow an attacker to gain full internal access to a network from the internet.

The technique exploits insecurely configured reverse web proxies to gain access to internal/DMZ systems.

This attack is based on an Apache web server which is using "modrewrite" to proxy web requests internally. Other proxies may suffer from this issue.

The vulnerability occurs if the Apache configuration file is configured like this:

RewriteRule ^(.) http://internalserver:80$1 [P]

As opposed to:

RewriteRule ^(.) http://internalserver:80/$1 [P]

It is important for readers to review their reverse proxy configurations to ensure that the rewrite rules are securely configured and cannot be abused in such a way that they can be used to compromise internal systems.