// For flags

CVE-2020-16126

accountsservice drops ruid, allows unprivileged users to send it signals

Severity Score

3.3
*CVSS v3.1

Exploit Likelihood

1.9%
*EPSS

Affected Versions

1
*CPE

Public Exploits

2
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

An Ubuntu-specific modification to AccountsService in versions before 0.6.55-0ubuntu13.2, among other earlier versions, improperly dropped the ruid, allowing untrusted users to send signals to AccountService, thus stopping it from handling D-Bus messages in a timely fashion.

Una modificación específica de Ubuntu para AccountsService en versiones anteriores a 0.6.55-0ubuntu13.2, entre otras versiones anteriores, eliminó incorrectamente el ruid, lo que permitió a usuarios que no eran de confianza enviar señales a AccountService, impidiendo así que manejara los mensajes D-Bus de manera oportuna

Kevin Backhouse discovered that AccountsService incorrectly dropped privileges. A local user could possibly use this issue to cause AccountsService to crash or hang, resulting in a denial of service. Kevin Backhouse discovered that AccountsService incorrectly handled reading .pam_environment files. A local user could possibly use this issue to cause AccountsService to crash or hang, resulting in a denial of service. This issue only affected Ubuntu 20.04 LTS and Ubuntu 20.10. Various other issues were also addressed.

*Credits: Kevin Backhouse
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low
Attack Vector
Local
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2020-07-29 CVE Reserved
  • 2020-11-03 CVE Published
  • 2020-11-17 First Exploit
  • 2024-09-16 CVE Updated
  • 2025-03-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-269: Improper Privilege Management
CAPEC
Affected Vendors, Products, and Versions (1)