CVE-2021-3999
Publication date 1 February 2022
Last updated 25 August 2025
Ubuntu priority
Cvss 3 Severity Score
Description
A flaw was found in glibc. An off-by-one buffer overflow and underflow in getcwd() may lead to memory corruption when the size of the buffer is exactly 1. A local attacker who can control the input buffer and size passed to getcwd() in a setuid program could use this flaw to potentially execute arbitrary code and escalate their privileges on the system.
Status
| Package | Ubuntu Release | Status | 
|---|---|---|
| eglibc | 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 2.19-0ubuntu6.15+esm3 
                                
                                   | |
| glibc | 24.04 LTS noble | 
                                Not affected 
                                
                               | 
| 22.04 LTS jammy | 
                                Not affected 
                                
                               | |
| 20.04 LTS focal | 
                                Fixed 2.31-0ubuntu9.7 
                                
                               | |
| 18.04 LTS bionic | 
                                Fixed 2.27-3ubuntu1.5 
                                
                               | |
| 16.04 LTS xenial | 
                                Fixed 2.23-0ubuntu11.3+esm1 
                                
                                   | 
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| Package | Patch details | 
|---|---|
| glibc | 
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 | High | 
| Availability impact | High | 
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | 
References
Related Ubuntu Security Notices (USN)
- USN-5310-1
- GNU C Library vulnerabilities
- 1 March 2022
- USN-5310-2
- GNU C Library vulnerabilities
- 7 March 2022
- USN-6762-1
- GNU C Library vulnerabilities
- 2 May 2024