To: bugtraq@securityfocus.com announce@lists.caldera.com scoannmod@xenitec.on.ca

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		Caldera International, Inc.  Security Advisory

Subject:		OpenServer 5.0.5 OpenServer 5.0.6 : Apache Web Server Chunk Handling Vulnerability / mod_ssl off-by-one error
Advisory number: 	CSSA-2002-SCO.32
Issue date: 		2002 July 01
Cross reference:
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1. Problem Description

	This advisory addresses two separate vulnerabilities:

	1) There is a remotely exploitable vulnerability in the
	   handling of large chunks of data in web servers that are
	   based on Apache source code.

	2) mod_ssl registers a rewrite_command hook when backward
	   compatibility is enabled. The ssl_compat_directive() is
	   called for every line read in a configuration file, and
	   contains an off-by-one error while doing so.


2. Vulnerable Supported Versions

	System				Subsystem
	----------------------------------------------------------------------
	OpenServer 5.0.5		Apache
	OpenServer 5.0.6		Apache


3. Solution

	The proper solution is to install the latest packages.


4. OpenServer 5.0.5

	4.1 Location of Fixed Binaries

	ftp://ftp.caldera.com/pub/updates/OpenServer/CSSA-2002-SCO.32


4.2 Verification

	MD5 (VOL.000.000) = 87ccdaa522968532ca4c64b7e22ed7d2

	md5 is available for download from
		ftp://ftp.caldera.com/pub/security/tools


4.3 Installing Fixed Binaries

	Upgrade the affected binaries with the following commands:

	1) Download the VOL* files to the /tmp directory

	Run the custom command, specify an install from media images,
	and specify the /tmp directory as the location of the images.


5. OpenServer 5.0.6

	5.1 Location of Fixed Binaries

	ftp://ftp.caldera.com/pub/updates/OpenServer/CSSA-2002-SCO.32


5.2 Verification

	MD5 (VOL.000.000) = 87ccdaa522968532ca4c64b7e22ed7d2

	md5 is available for download from
		ftp://ftp.caldera.com/pub/security/tools


5.3 Installing Fixed Binaries

	Upgrade the affected binaries with the following commands:

	1) Download the VOL* files to the /tmp directory

	Run the custom command, specify an install from media images,
	and specify the /tmp directory as the location of the images.


6. References

	Specific references for this advisory:
		http://www.cert.org/advisories/CA-2002-17.html
http://httpd.apache.org/info/security_bulletin_20020617.txt
http://www.modssl.org/

Caldera security resources:
		http://www.caldera.com/support/security/index.html

This security fix closes Caldera incidents sr865897, fz521278,
	erg712081.


7. Disclaimer

	Caldera International, Inc. is not responsible for the
	misuse of any of the information we provide on this website
	and/or through our security advisories. Our advisories are
	a service to our customers intended to promote secure
	installation and use of Caldera products.


8. Acknowledgements

	Neel Mehta of the ISS X-Force discovered the Apache
	vulnerability. Mark Litchfield reported the vulnerability
	to the Apache Software Foundation, and Mark Cox reported
	it to the CERT/CC.

	The mod_ssl vulnerability information was obtained from an
	advisory by Frank Denis (j@pureftpd.org)