OpenSSL Server Key exchange message denial of service
| openssl-serverkey-dos (42667) |  Medium Risk |
Description:
OpenSSL is vulnerable to a denial of service, caused by a NULL pointer dereference error when the server omits the "Server Key exchange message" from the TLS handshake. By persuading a victim to connect to a malicious server with certain cipher suites, a remote attacker could exploit this vulnerability to cause the client to crash.
*CVSS:
| Base Score: | 4.3 |
| Access Vector: | Network |
| Access Complexity: | Medium |
| Authentication: | None |
| Confidentiality Impact: | None |
| Integrity Impact: | None |
| Availability Impact: | Partial |
| Temporal Score: | 3.2 |
| Exploitability: | Unproven |
| Remediation Level: | Official-Fix |
| Report Confidence: | Confirmed |
Consequences:
Denial of Service
Remedy:
Upgrade to the latest version of OpenSSL (0.9.8h or later), available from the OpenSSL Web site. See References.
References:
- NORTEL BULLETIN ID: 2008008922, Rev 1: Nortel Response to 2 Potential DoS Vulnerabilities in OpenSSL.
- OpenSSL Security Advisory [28-Mar-2008]: Two moderate severity security flaws have been fixed in OpenSSL 0.9.8h.
- OpenSSL Web site: OpenSSL: Source, Tarballs.
- BID-29405: OpenSSL Multiple Denial of Service Vulnerabilities
- CVE-2008-1672: OpenSSL 0.9.8f and 0.9.8g allows remote attackers to cause a denial of service (crash) via a TLS handshake that omits the Server Key Exchange message and uses particular cipher suites
- GLSA-200806-08: OpenSSL: Denial of Service
- MDVSA-2008:107: Updated openssl package fixes denial of service vulnerabilities
- SA30405: OpenSSL Two Denial of Service Vulnerabilities
- SA30852: Nortel Media Processing Server OpenSSL Multiple Vulnerabilities
- SA31228: cwRsync OpenSSL Denial of Service Vulnerabilities
- SECTRACK ID: 1020122: OpenSSL TLS Handshake Bug Lets Remote Servers Crash the Connected Client
- US-CERT VU#520586: OpenSSL TLS handshake Denial of Service
- USN-620-1: OpenSSL vulnerabilities
- VUPEN/ADV-2008-1680: OpenSSL Server Name Extension and Key Exchange Vulnerabilities
- VUPEN/ADV-2008-1937: Nortel Media Processing Server Multiple OpenSSL Vulnerabilities
Platforms Affected:
- Canonical Ubuntu 8.04 LTS
- Gentoo Linux
- MandrakeSoft Mandrake Linux 2008.1 X86_64
- MandrakeSoft Mandrake Linux 2008.1
- OpenSSL OpenSSL 0.9.8f
- OpenSSL OpenSSL 0.9.8g
Reported:
May 28, 2008
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The information within this database may change without notice. Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. In no event shall IBM be held liable for any damages whatsoever arising out of or in connection with the use or spread of this information.