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Red Hat Secure Web Server 3.2 RHSA-2002:117-11 Moderate: DoS Attack

The Apache Web server contains a security vulnerability which can be usedto launch a denial of service attack, or in some cases, allow remote codeexecution.. ` --------------------------------------------------------------------- Red Hat, Inc. Red Hat Security Advisory Synopsis: Updated secureweb packages fix chunked encoding issue Advisory ID: RHSA-2002:117-11 Issue date: 2002-06-18 Updated on: 2002-06-26 Product: Red Hat Secure Web Server Keywords: apache chunked encoding DoS Cross references: RHSA-2002:103 Obsoletes: RHSA-2002:042 CVE Names: CAN-2002-0392 --------------------------------------------------------------------- 1. Topic: The Apache Web server contains a security vulnerability which can be used to launch a denial of service attack, or in some cases, allow remote code execution. Red Hat Secure Web server is based on the Apache Web server and the secureweb package has been updated to fix this denial of service vulnerability. 2. Relevant releases/architectures: Red Hat Secure Web Server 3.2 - i386 3. Problem description: Versions of the Apache Web server up to and including 1.3.24 contain a bug in the routines which deal with requests that are processed with "chunked" encoding. A carefully crafted invalid request can cause an Apache child process to call the memcpy() function in a way that will write past the end of its buffer, corrupting the stack. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2002-0392 to this issue. Our investigations show that this bug cannot be used to gain remote access to a server running Red Hat Secure Web Server but it does cause the child process to die. The Apache parent process will notice this and start a new child process when necessary -- using slightly more resources than normal. All users of Secure Web Server should update to these errata packages to correct this security issue. NOTE: Pay special attention to theinstallation instructions in the "Solution" section below as they differ from standard upgrade instructions. 4. Solution: Before applying this update, make sure all previously released errata relevant to your system have been applied. Some of these files are distributed in rhmask format and may only be used by individuals who have purchased Red Hat Linux 6.2 Professional. To produce installable RPM files from the rhmask files, retrieve the rhmask files via ftp and type the following command: rhmask secureweb-3.2-12.i386.rpm secureweb-3.2.5-1.i386.rpm.rhmask The original RPM is located only on your Secure Web Server CD, and cannot be obtained via the Internet. Note: If you do not have the original RPM located in the same directory as the rhmask file, you will need to prefix the name of the RPM with the full path name to its location (for example, on your installation CD). To update all RPMs for your particular architecture, run: rpm -Fvh [filenames] where [filenames] is a list of the RPMs you wish to upgrade. Only those RPMs which are currently installed will be updated. Those RPMs which are not installed but included in the list will not be updated. Note that you can also use wildcards (*.rpm) if your current directory *only* contains the desired RPMs. 5. Bug IDs fixed ( for more info): 6. RPMs required: Red Hat Secure Web Server 3.2: SRPMS: i386: 7. Verification: MD5 sum Package Name -------------------------------------------------------------------------- 20dae29b7188c307cd495ee7509ff231 other_prod/secureweb/3.2/SRPMS/secureweb-3.2.6-1.nosrc.rpm 0ab5997be631fdee7d000b6d6767ed0d other_prod/secureweb/3.2/i386/secureweb-3.2.6-1.i386.rpm.rhmask eb4d09fb8452f62d02e443bdaea0bbd9 other_prod/secureweb/3.2/i386/secureweb-devel-3.2.6-1.i386.rpm 0ebbcd3faadd569717fb85caf5b18320 other_prod/secureweb/3.2/i386/secureweb-manual-3.2.6-1.i386.rpm These packages are GPG signed by Red Hat, Inc. for security. Our key is available at: About You can verifyeach package with the following command: rpm --checksig If you only wish to verify that each package has not been corrupted or tampered with, examine only the md5sum with the following command: rpm --checksig --nogpg 8. References: apache Apache Week. Security issue forces release of 1.3.26, 2.0.39 CVE -CVE-2002-0392 Copyright(c) 2000, 2001, 2002 Red Hat, Inc. `. The Apache Web Server faces a Moderate DoS issue, demanding urgent action to safeguard systems from possible attack.. Red Hat Secure Web, DoS Attack, Apache Server Security, Attack Prevention. . Severity: Important. LinuxSecurity.com Team

Jun 26, 2002 •Important Red Hat