CVE-2021-23971
Publication date 26 February 2021
Last updated 25 August 2025
Ubuntu priority
Cvss 3 Severity Score
Description
When processing a redirect with a conflicting Referrer-Policy, Firefox would have adopted the redirect’s Referrer-Policy. This would have potentially resulted in more information than intended by the original origin being provided to the destination of the redirect. This vulnerability affects Firefox < 86.
Status
| Package | Ubuntu Release | Status | 
|---|---|---|
| firefox | 24.04 LTS noble | 
                              
                               
                                Fixed 86.0+build3-0ubuntu1 
                                
                               
                             |      
                          
                            
                          
                        
                      
| 22.04 LTS jammy | 
                              
                               
                                Fixed 86.0+build3-0ubuntu1 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 20.04 LTS focal | 
                              
                               
                                Fixed 86.0+build3-0ubuntu0.20.04.1 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 18.04 LTS bionic | 
                              
                               
                                Fixed 86.0+build3-0ubuntu0.18.04.1 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 16.04 LTS xenial | 
                              
                               
                                Fixed 86.0+build3-0ubuntu0.16.04.1 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 14.04 LTS trusty | Not in release | |
| mozjs38 | 24.04 LTS noble | Not in release | 
| 22.04 LTS jammy | Not in release | |
| 20.04 LTS focal | Not in release | |
| 18.04 LTS bionic | Ignored | |
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| mozjs52 | 24.04 LTS noble | Not in release | 
| 22.04 LTS jammy | Not in release | |
| 20.04 LTS focal | Ignored | |
| 18.04 LTS bionic | Ignored | |
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| mozjs60 | 24.04 LTS noble | Not in release | 
| 22.04 LTS jammy | Not in release | |
| 20.04 LTS focal | Not in release | |
| 18.04 LTS bionic | Not in release | |
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| mozjs68 | 24.04 LTS noble | Not in release | 
| 22.04 LTS jammy | Not in release | |
| 20.04 LTS focal | Ignored | |
| 18.04 LTS bionic | Not in release | |
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| mozjs78 | 24.04 LTS noble | Not in release | 
| 22.04 LTS jammy | Ignored | |
| 20.04 LTS focal | Not in release | |
| 18.04 LTS bionic | Not in release | |
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | 
Notes
Severity score breakdown
| Parameter | Value | 
|---|---|
| Base score | 
                      
                      
                         | 
                  
| Attack vector | Network | 
| Attack complexity | Low | 
| Privileges required | None | 
| User interaction | Required | 
| Scope | Unchanged | 
| Confidentiality | High | 
| Integrity impact | None | 
| Availability impact | None | 
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N | 
References
Related Ubuntu Security Notices (USN)
- USN-4756-1
 - Firefox vulnerabilities
 - 26 February 2021