Cross-site scripting vulnerability in the mod_ssl Apache module 2.8.9 and earlier, when UseCanonicalName is off and wildcard DNS is enabled, allows remote attackers to execute script as other web site visitors, via the server name in an HTTPS response on the SSL port, which is used in a self-referencing URL, a different vulnerability than CAN-2002-0840.

Joe Orton discovered a cross site scripting problem in mod_ssl, an Apache module that adds Strong cryptography (i.e. HTTPS support) to the webserver. The module will return the server name unescaped in the response to an HTTP request on an SSL port.

Like the other recent Apache XSS bugs, this only affects servers using a combination of 'UseCanonicalName off' (default in the Debian package of Apache) and wildcard DNS. This is very unlikely to happen, though.
Apache 2.0/mod_ssl is not vulnerable since it already escapes this HTML.

With this setting turned on, whenever Apache needs to construct a self-referencing URL (a URL that refers back to the server the response is coming from) it will use ServerName and Port to form a 'canonical' name. With this setting off, Apache will use the hostname:port that the client supplied, when possible. This also affects SERVER_NAME and SERVER_PORT in CGI scripts.

The remote host is running a version of Apache which is older than 1.3.27. This version contains several flaws that have been fixed in 1.3.27.

The remote host is using a version of mod_ssl which is older than 2.8.10. This version is vulnerable to a flaw which may allow an attacker to successfully perform a cross-site scripting attack. *** Note that several Linux distributions (such as RedHat) patched this CGI without increasing its version number, therefore this might be a false positive.

A cross-site scripting vulnerability was discovered in mod_ssl by Joe Orton. This only affects servers using a combination of wildcard DNS and 'UseCanonicalName off' (which is not the default in Mandrake Linux). With this setting turned off, Apache will attempt to use the hostname:port that the client supplies, which is where the problem comes into play. With this setting turned on (the default), Apache constructs a self-referencing URL and will use ServerName and Port to form the canonical name.

It is recommended that all users upgrade, regardless of the setting of the 'UseCanonicalName' configuration option.

Updated apache and httpd packages are available which fix a number of security issues for Red Hat Linux Advanced Server 2.1.

[Updated 06 Feb 2003] Added fixed packages for Advanced Workstation 2.1

The Apache HTTP server is a powerful, full-featured, efficient, and freely-available Web server.

Buffer overflows in the ApacheBench support program (ab.c) in Apache versions prior to 1.3.27 allow a malicious Web server to cause a denial of service and possibly execute arbitrary code via a long response. The Common Vulnerabilities and Exposures project has assigned the name CVE-2002-0843 to this issue.

Two cross-site scripting vulnerabilities are present in the error pages for the default '404 Not Found' error, and for the error response when a plain HTTP request is received on an SSL port. Both of these issues are only exploitable if the 'UseCanonicalName' setting has been changed to 'Off', and wildcard DNS is in use. These issues would allow remote attackers to execute scripts as other Web page visitors, for instance, to steal cookies. These issues affect versions of Apache 1.3 before 1.3.26, and versions of mod_ssl before 2.8.12.
The Common Vulnerabilities and Exposures project has assigned the names CVE-2002-0840 and CVE-2002-1157 to these issues.

The shared memory scoreboard in the HTTP daemon for Apache 1.3, prior to version 1.3.27, allowed a user running as the 'apache' UID to send a SIGUSR1 signal to any process as root, resulting in a denial of service (process kill) or other such behavior that would not normally be allowed. The Common Vulnerabilities and Exposures project has assigned the name CVE-2002-0839 to this issue.

All users of the Apache HTTP server are advised to upgrade to the applicable errata packages. For Red Hat Linux Advanced Server 2.1 these packages include Apache version 1.3.27 which is not vulnerable to these issues.

Note that the instructions in the 'Solution' section of this errata contain additional steps required to complete the upgrade process.

According to the web server banner, the version of mod_ssl running on the remote host has a cross-site scripting vulnerability. A remote attacker could exploit this by tricking a user into requesting a maliciously crafted URL, resulting in stolen credentials.

Note that several Linux distributions (such as RedHat) patched the old version of this module.  Therefore, this might be a false positive. Please check with your vendor to determine if you really are affected by this flaw.

ID	Name	Product	Family	Severity
15018	Debian DSA-181-1 : libapache-mod-ssl - XSS	Nessus	Debian Local Security Checks	high
1488	Apache < 1.3.27 Multiple Vulnerabilities	Nessus Network Monitor	Web Servers	high
1529	mod_ssl < 2.8.10 Wildcard DNS Server Name XSS	Nessus Network Monitor	Web Servers	low
13972	Mandrake Linux Security Advisory : mod_ssl (MDKSA-2002:072)	Nessus	Mandriva Local Security Checks	high
12332	RHEL 2.1 : apache (RHSA-2002:251)	Nessus	Red Hat Local Security Checks	high
11622	Apache mod_ssl Host: Header XSS	Nessus	CGI abuses : XSS	medium

Detections

Analytics

CVE-2002-1157

medium

Tenable Plugins

high

high

low

high

high

medium