CVE-2025-3931 is a high-severity local privilege escalation vulnerability found in Yggdrasil, a system broker component used in Red Hat Enterprise Linux 10. Yggdrasil facilitates inter-process communication among child "worker" processes via the DBus messaging system. The vulnerability arises because Yggdrasil exposes a DBus method for dispatching messages to these workers without implementing any authentication or authorization checks. This design flaw allows any local system user to invoke this method. One of the workers acts as a package manager with the ability to create and enable software repositories and install or remove RPM packages. Exploiting this flaw, an attacker with local access can coerce the package manager worker to install arbitrary RPM packages, effectively escalating their privileges on the system. This can lead to full system compromise by allowing unauthorized access and modification of sensitive system data. The CVSS v3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability, with low attack complexity and requiring only low privileges but no user interaction. No known exploits are currently reported in the wild, but the vulnerability’s nature makes it a significant risk for systems running the affected Red Hat Enterprise Linux 10 version. The lack of authentication on a critical system communication channel represents a serious design oversight that could be leveraged by malicious insiders or attackers who have gained limited local access to escalate privileges and gain full control over the system.

For European organizations using Red Hat Enterprise Linux 10, this vulnerability poses a significant risk. An attacker with local access—such as a malicious insider, compromised user account, or attacker who has gained limited foothold through other means—can escalate privileges to root level. This can lead to unauthorized installation of software, modification or deletion of critical system files, and potential deployment of persistent malware or backdoors. The compromise of confidentiality, integrity, and availability can disrupt business operations, lead to data breaches involving sensitive or regulated information, and cause compliance violations under GDPR and other European data protection laws. Organizations relying on Red Hat Enterprise Linux 10 in critical infrastructure, financial services, healthcare, or government sectors are particularly at risk due to the potential for systemic impact and regulatory consequences. The vulnerability’s exploitation could also facilitate lateral movement within networks, increasing the scope of compromise.

1. Immediate application of vendor patches once available is critical; monitor Red Hat advisories closely for updates addressing CVE-2025-3931. 2. Until patches are released, restrict local user access to systems running Red Hat Enterprise Linux 10 to trusted personnel only, minimizing the risk of exploitation. 3. Implement strict access controls and monitoring on DBus communications, potentially using AppArmor or SELinux policies to limit which processes can interact with Yggdrasil workers. 4. Employ system integrity monitoring to detect unauthorized package installations or repository changes. 5. Conduct regular audits of installed packages and repository configurations to identify anomalies. 6. Use multi-factor authentication and strong user account management to reduce the likelihood of unauthorized local access. 7. Deploy endpoint detection and response (EDR) solutions capable of detecting suspicious local privilege escalation activities. 8. Educate system administrators and security teams about this vulnerability to ensure rapid detection and response.