CVE-2021-3560

Status: AnalyzedHigh (7.8)⚠ Active exploitation

It was found that polkit could be tricked into bypassing the credential checks for D-Bus requests, elevating the privileges of the requestor to the root user. This flaw could be used by an unprivileged local attacker to, for example, create a new local administrator. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Base score: 7.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 24%
Percentile among all scored CVEs: 98
Score date: 10/5/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

CISA KEV — actively exploited

Added to catalog: 5/12/2023
Remediation due date: 6/2/2023
Known ransomware use: Unknown

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1068 Exploitation for Privilege Escalationprivilege escalation95 %
Primary impactT1078 Valid Accountsstealth · persistence · privilege escalation · initial access90 %
Secondary impactT1059 Command and Scripting Interpreterexecution80 %

Vulnerabilidad de escalada de privilegios local (AV:L, PR:L) que permite bypass de verificación de credenciales en polkit para obtener acceso root. Facilita creación de cuentas administrativas (T1078) y ejecución de comandos privilegiados (T1059).

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Privileged Account Management Execution Prevention Application Developer Guidance Active Directory Configuration User Training User Account Management

Affected technologies (6)

Canonical — Ubuntu Linux Debian — Debian Linux Polkit Project — Polkit Redhat — Openshift Container Platform Redhat — Virtualization Redhat — Virtualization Host

CWEs

CWE-863
CWE-754

References

Raw JSON (NVD)

Show

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