CVE-2023-28366
Publication date 1 September 2023
Last updated 27 June 2025
Ubuntu priority
Cvss 3 Severity Score
Description
The broker in Eclipse Mosquitto 1.3.2 through 2.x before 2.0.16 has a memory leak that can be abused remotely when a client sends many QoS 2 messages with duplicate message IDs, and fails to respond to PUBREC commands. This occurs because of mishandling of EAGAIN from the libc send function.
Status
| Package | Ubuntu Release | Status | 
|---|---|---|
| mosquitto | ||
| 22.04 LTS jammy | 
                              
                               
                                Fixed 2.0.11-1ubuntu1.1 
                                
                               
                             |      
                          
                            
                          
                        
                      |
| 20.04 LTS focal | Ignored backporting risks regressions | |
| 18.04 LTS bionic | Ignored backporting risks regressions | |
| 16.04 LTS xenial | Ignored backporting risks regressions | |
| 14.04 LTS trusty | 
                              
                               
                                Not affected 
                                
                               
                             |      
                          
                            
                          
                        
                      
Notes
gianz
Memory leak requiring refactoring of core functions to be fixed. Applying the patches to versions < 2.0.0 is likely to cause regressions.
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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | 
References
Related Ubuntu Security Notices (USN)
- USN-6492-1
 - Mosquitto vulnerabilities
 - 21 November 2023
 
Other references
- https://mosquitto.org/blog/2023/08/version-2-0-16-released/
 - https://github.com/eclipse/mosquitto/commit/6113eac95a9df634fbc858be542c4a0456bfe7b9 (v2.0.16)
 - https://github.com/eclipse/mosquitto/commit/6113eac95a9df634fbc858be542c4a0456bfe7b9
 - https://www.compass-security.com/fileadmin/Research/Advisories/2023_02_CSNC-2023-001_Eclipse_Mosquitto_Memory_Leak.txt
 - https://github.com/eclipse/mosquitto/compare/v2.0.15...v2.0.16
 - https://www.cve.org/CVERecord?id=CVE-2023-28366