CVE-2021-23968
Publication date 26 February 2021
Last updated 25 August 2025
Ubuntu priority
Cvss 3 Severity Score
Description
If Content Security Policy blocked frame navigation, the full destination of a redirect served in the frame was reported in the violation report; as opposed to the original frame URI. This could be used to leak sensitive information contained in such URIs. This vulnerability affects Firefox < 86, Thunderbird < 78.8, and Firefox ESR < 78.8.
Status
| Package | Ubuntu Release | Status | 
|---|---|---|
| thunderbird | 24.04 LTS noble | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      
| 22.04 LTS jammy | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 20.04 LTS focal | 
                              
                               
                                Fixed 1:78.8.1+build1-0ubuntu0.20.04.1 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 18.04 LTS bionic | 
                              
                               
                                Fixed 1:78.8.1+build1-0ubuntu0.18.04.1 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 16.04 LTS xenial | Ignored end of standard support, was needed | |
| 14.04 LTS trusty | Not in release | |
| 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 | |
| firefox-esr | 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 | |
| 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 | Low | 
| Integrity impact | None | 
| Availability impact | None | 
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N | 
References
Related Ubuntu Security Notices (USN)
- USN-4756-1
 - Firefox vulnerabilities
 - 26 February 2021
 - USN-4936-1
 - Thunderbird vulnerabilities
 - 6 May 2021
 
Other references
- https://www.mozilla.org/en-US/security/advisories/mfsa2021-07/#CVE-2021-23968
 - https://www.mozilla.org/en-US/security/advisories/mfsa2021-08/#CVE-2021-23968
 - https://www.mozilla.org/en-US/security/advisories/mfsa2021-09/#CVE-2021-23968
 - https://bugzilla.mozilla.org/show_bug.cgi?id=1687342
 - https://www.mozilla.org/security/advisories/mfsa2021-07/
 - https://www.mozilla.org/security/advisories/mfsa2021-08/
 - https://www.mozilla.org/security/advisories/mfsa2021-09/
 - https://www.cve.org/CVERecord?id=CVE-2021-23968