CVE-2018-1061
Publication date 19 June 2018
Last updated 25 August 2025
Ubuntu priority
Cvss 3 Severity Score
Description
python before versions 2.7.15, 3.4.9, 3.5.6rc1, 3.6.5rc1 and 3.7.0 is vulnerable to catastrophic backtracking in the difflib.IS_LINE_JUNK method. An attacker could use this flaw to cause denial of service.
Status
| Package | Ubuntu Release | Status | 
|---|---|---|
| python3.4 | ||
| 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 | 
                              
                               
                                Fixed 3.4.3-1ubuntu1~14.04.7 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| python3.5 | ||
| 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 | 
                              
                               
                                Fixed 3.5.2-2ubuntu0~16.04.5 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 14.04 LTS trusty | 
                              
                               
                                Fixed 3.5.2-2ubuntu0~16.04.4~14.04.1+esm1 
                                
                                   
                             |      
                          
                            
                          
                        
                      |
| python2.7 | ||
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 20.04 LTS focal | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 18.04 LTS bionic | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 16.04 LTS xenial | 
                              
                               
                                Fixed 2.7.12-1ubuntu0~16.04.4 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 14.04 LTS trusty | 
                              
                               
                                Fixed 2.7.6-8ubuntu0.5 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| python3.6 | ||
| 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 affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | |
| python3.7 | ||
| 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 affected 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release | 
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Patch details
| Package | Patch details | 
|---|---|
| python3.4 | 
                        
  | 
                    
| python3.5 | 
                        
  | 
                    
| python2.7 | 
                        
  | 
                    
| python3.6 | 
                        
  | 
                    
| python3.7 | 
                        
  | 
                    
Severity score breakdown
| Parameter | Value | 
|---|---|
| Base score | 
                      
                      
                         | 
                  
| Attack vector | Network | 
| Attack complexity | Low | 
| Privileges required | None | 
| User interaction | None | 
| Scope | Unchanged | 
| Confidentiality | None | 
| Integrity impact | None | 
| Availability impact | High | 
| Vector | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | 
References
Related Ubuntu Security Notices (USN)
- USN-3817-1
 - Python vulnerabilities
 - 13 November 2018
 - USN-3817-2
 - Python vulnerabilities
 - 15 November 2018
 - USN-6891-1
 - Python vulnerabilities
 - 11 July 2024