CVE-2021-3939
HIGHDescription
Ubuntu-specific modifications to accountsservice (in patch file debian/patches/0010-set-language.patch) caused the fallback_locale variable, pointing to static storage, to be freed, in the user_change_language_authorized_cb function. This is reachable via the SetLanguage dbus function. This is fixed in versions 0.6.55-0ubuntu12~20.04.5, 0.6.55-0ubuntu13.3, 0.6.55-0ubuntu14.1.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Exploit Intelligence
Low risk: more likely to be exploited than 27% of all known CVEs.
References
Related Vulnerabilities
Other CWE-590 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2020-6016 | Critical | 9.8 | 5.8% | - | Fix |
| CVE-2022-31625 | High | 8.1 | 3.4% | - | Fix |
| CVE-2021-42377 | Critical | 9.8 | 3.4% | - | Fix |
| CVE-2022-31627 | High | 7.7 | 2.0% | - | Fix |
| CVE-2023-25565 | High | 7.5 | 1.1% | - | Fix |
| CVE-2025-32911 | Critical | 9.0 | 0.9% | - | Fix |
Common questions
How do I fix CVE-2021-3939?
Published advisories record a fix for 2 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.
Is CVE-2021-3939 being actively exploited?
Not that we know of. CVE-2021-3939 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.35% is the estimated probability that it will be exploited in the next 30 days. That is higher than 27% of all scored CVEs.
How severe is CVE-2021-3939?
CVE-2021-3939 has a CVSS v3 base score of 7.8, rated high. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2021-3939 affect?
Published advisories record a fix for accountsservice (Ubuntu), libaccountsservice0 (Ubuntu). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2021-3939
Markdown
[](https://tridentstack.com/cve/CVE-2021-3939)HTML
<a href="https://tridentstack.com/cve/CVE-2021-3939"><img src="https://tridentstack.com/cve/badge/CVE-2021-3939.svg" alt="CVE-2021-3939"></a>Find and fix vulnerabilities across your fleet
TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.
This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.