CVE-2016-3713
Publication date 16 May 2016
Last updated 25 August 2025
Ubuntu priority
Cvss 3 Severity Score
Description
The msr_mtrr_valid function in arch/x86/kvm/mtrr.c in the Linux kernel before 4.6.1 supports MSR 0x2f8, which allows guest OS users to read or write to the kvm_arch_vcpu data structure, and consequently obtain sensitive information or cause a denial of service (system crash), via a crafted ioctl call.
From the Ubuntu Security Team
David Matlack discovered that the Kernel-based Virtual Machine (KVM) implementation in the Linux kernel did not properly restrict variable Memory Type Range Registers (MTRR) in KVM guests. A privileged user in a guest VM could use this to cause a denial of service (system crash) in the host, expose sensitive information from the host, or possibly gain administrative privileges in the host.
Status
| Package | Ubuntu Release | Status | 
|---|---|---|
| linux | ||
| 16.04 LTS xenial | 
                              
                               
                                Fixed 4.4.0-22.40 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 14.04 LTS trusty | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| linux-aws | ||
| 16.04 LTS xenial | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 14.04 LTS trusty | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| linux-flo | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-gke | ||
| 16.04 LTS xenial | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 14.04 LTS trusty | Not in release | |
| linux-goldfish | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-grouper | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-hwe | ||
| 16.04 LTS xenial | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 14.04 LTS trusty | Not in release | |
| linux-hwe-edge | ||
| 16.04 LTS xenial | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 14.04 LTS trusty | Not in release | |
| linux-lts-raring | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-lts-saucy | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-lts-trusty | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-lts-utopic | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-lts-vivid | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-lts-wily | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | 
                              
                               
                                Fixed 4.2.0-36.42~14.04.1 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| linux-lts-xenial | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | 
                              
                               
                                Fixed 4.4.0-22.40~14.04.1 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| linux-maguro | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-mako | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-manta | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-raspi2 | ||
| 16.04 LTS xenial | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 14.04 LTS trusty | Not in release | |
| linux-snapdragon | ||
| 16.04 LTS xenial | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 14.04 LTS trusty | Not in release | |
| linux-armadaxp | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-linaro-omap | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-linaro-shared | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-linaro-vexpress | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-lts-quantal | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-qcm-msm | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| linux-ti-omap4 | ||
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
Notes
Severity score breakdown
| Parameter | Value | 
|---|---|
| Base score | 
                      
                      
                         | 
                  
| Attack vector | Local | 
| Attack complexity | Low | 
| Privileges required | Low | 
| User interaction | None | 
| Scope | Unchanged | 
| Confidentiality | High | 
| Integrity impact | None | 
| Availability impact | High | 
| Vector | CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H | 
References
Related Ubuntu Security Notices (USN)
- USN-2978-2
 - Linux kernel (Wily HWE) vulnerabilities
 - 16 May 2016
 - USN-2979-2
 - Linux kernel (Xenial HWE) vulnerabilities
 - 16 May 2016
 - USN-2979-1
 - Linux kernel vulnerabilities
 - 16 May 2016
 - USN-2978-1
 - Linux kernel vulnerabilities
 - 16 May 2016