Xen para-virtualized framebuffer (PVFB) ioemu denial of service
| xen-pvfb-ioemu-dos (43362) |  Medium Risk |
Description:
The Xen para-virtualized framebuffer (PVFB) backend is vulnerable to a denial of service, caused by improper frame buffer restrictions in Xen ioemu. By mapping an arbitrary amount of guest memory, a local attacker could exploit this vulnerability to crash the application.
*CVSS:
| Base Score: | 2.1 |
| Access Vector: | Local |
| Access Complexity: | Low |
| Authentication: | None |
| Confidentiality Impact: | None |
| Integrity Impact: | None |
| Availability Impact: | Partial |
| Temporal Score: | 1.6 |
| Exploitability: | Unproven |
| Remediation Level: | Official-Fix |
| Report Confidence: | Confirmed |
Consequences:
Denial of Service
Remedy:
Refer to Xen changeset 9044705960cb for patch, upgrade or suggested workaround information. See References.
References:
- oss-security Mailing List, Wed, 21 May 2008 19:15:00 +0200: New Xen ioemu: PVFB backend issue.
- Xen changeset 9044705960cb: Fix PVFB backend to limit frame buffer size.
- xen-devel Mailing List, Thu, 15 May 2008 09:53:01 +0200: ioemu: Fix PVFB backend to limit frame buffer size.
- BID-30646: Xen Para Virtualized Frame Buffer 'ioemu' Frontend Frame Buffer Denial of Service Vulnerability
- CVE-2008-1952: The backend for XenSource Xen Para Virtualized Frame Buffer (PVFB) in Xen ioemu does not properly restrict the frame buffer size, which allows attackers to cause a denial of service (crash) by mapping an arbitrary amount of guest memory.
- RHSA-2008-0892: Important: xen security and bug fix update
- SECTRACK ID: 1020957: Xen Hypervisor PVFB Validation Bug Lets Local Users Deny Service and May Let Local Users Gain Elevated Privileges
Platforms Affected:
- RedHat Enterprise Linux 5 Client
- RedHat Enterprise Linux 5
- RedHat RHEL Desktop Multi OS 5 Client
- RedHat RHEL Virtualization 5 Server
- XenSource Xen
Reported:
May 13, 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.