CVE-2026-59677 in policycoreutils
Summary
by MITRE • 07/23/2026
A Missing Authorization vulnerability in selinux policycoreutils seunshares allows a user that is running in unconfined context to kill e.g. root-owned processes running also in unconfined context
This issue affects policycoreutils through 3.10.
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Analysis
by VulDB Data Team • 07/23/2026
The vulnerability described represents a critical authorization flaw within the selinux policycoreutils package, specifically affecting versions through 3.10. This missing authorization issue occurs when a user operating within an unconfined SELinux context can potentially terminate processes owned by root that are also running in unconfined contexts. The fundamental problem lies in the improper enforcement of access controls that should normally prevent users from manipulating processes they do not own, regardless of whether those processes are running under the same security context. This weakness directly violates core security principles and creates a serious privilege escalation vector within systems utilizing SELinux policies.
The technical implementation of this vulnerability stems from insufficient permission checks within the seunshares component of policycoreutils. When processes operate in unconfined contexts, they should still be subject to proper authorization controls that prevent unauthorized termination of other processes, particularly those owned by privileged users like root. The flaw manifests when the system fails to properly validate that a user attempting to kill a process has appropriate authorization rights based on the target process's ownership and security context. This misconfiguration allows for arbitrary process termination across different user namespaces within the same unconfined domain, effectively bypassing normal SELinux access control mechanisms.
The operational impact of this vulnerability extends beyond simple privilege escalation to create potential system stability and security risks. An attacker with access to an unconfined user account could theoretically terminate critical root-owned services or processes, potentially causing system instability or service disruption. This capability becomes particularly dangerous when combined with other exploitation techniques that might allow an attacker to escalate privileges further or maintain persistent access to systems. The vulnerability essentially creates a backdoor mechanism for process manipulation that bypasses normal security boundaries and could be exploited in conjunction with other attacks to achieve more comprehensive compromise.
From a cybersecurity framework perspective, this vulnerability aligns with CWE-284 (Improper Access Control) and represents a direct violation of the principle of least privilege. The ATT&CK framework categorizes this issue under Privilege Escalation techniques where adversaries leverage system weaknesses to gain elevated permissions. Organizations utilizing SELinux policies are particularly at risk since this flaw undermines the fundamental security model that separates user contexts and enforces access controls between different security domains. The vulnerability essentially creates an unauthorized process management capability that should be restricted to privileged users only.
Mitigation strategies should focus on immediate patching of policycoreutils to versions that address the authorization gap in seunshares functionality. System administrators should also consider implementing additional monitoring for unauthorized process termination events, particularly when root-owned processes are targeted by unprivileged users. The broader security posture can be improved through regular SELinux policy audits and ensuring proper enforcement of access controls even within unconfined contexts. Organizations should also implement principle of least privilege practices, limiting the number of users with access to unconfined contexts where possible. Additional defensive measures include implementing process monitoring tools that can detect anomalous termination patterns and establishing incident response procedures specifically addressing unauthorized process manipulation activities.