SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2025-3931

A flaw was found in Yggdrasil, which acts as a system broker, allowing the processes to communicate to other children's "worker" processes through the DBus component.

HIGH 7.8EPSS 0.18%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.18%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A flaw was found in Yggdrasil, which acts as a system broker, allowing the processes to communicate to other children's "worker" processes through the DBus component. Yggdrasil creates a DBus method to dispatch messages to workers. However, it misses authentication and authorization checks, allowing every system user to call it. One available Yggdrasil worker acts as a package manager with capabilities to create and enable new repositories and install or remove packages. This flaw allows an attacker with access to the system to leverage the lack of authentication on the dispatch message to force the Yggdrasil worker to install arbitrary RPM packages. This issue results in local privilege escalation, enabling the attacker to access and modify sensitive system data.

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.18% probability · 8th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-280
Source
secalert@redhat.com
EPSS trend
0%3%5%27 October 2026: 0.18%27 October 202627 October 2026

EPSS 0.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.