Race Condition Vulnerability in libcap Affects Red Hat Products

CVE-2026-4878

What is CVE-2026-4878?

CVE-2026-4878 is a vulnerability identified in the libcap library, which is essential for managing POSIX capabilities in Linux systems. This library allows applications to set and manage file capabilities, providing granular control over permissions and access rights without requiring full root privileges. The identified flaw is a Time-of-check-to-time-of-use (TOCTOU) race condition in the cap_set_file() function. An attacker with write access to a parent directory can exploit this vulnerability to redirect file capability updates to a file under their control. This manipulation can enable the attacker to inject or strip capabilities from executable files, ultimately leading to privilege escalation. Such escalation can allow unauthorized users to execute sensitive operations or access protected resources, significantly undermining an organization's security posture.

Potential impact of CVE-2026-4878

1. Privilege Escalation: The primary risk associated with this vulnerability is the potential for an attacker to gain higher privileges than intended. By manipulating file capabilities, an unprivileged user could elevate their access rights, which can lead to unauthorized system changes or data access.

2. Security Breaches: If exploited, the vulnerability may allow attackers to compromise sensitive applications and data. This can lead to severe security incidents, including data breaches, where confidential information may be exposed or manipulated.

3. System Integrity Compromise: The ability to alter file capabilities can result in the execution of malicious code with elevated privileges. This not only jeopardizes the integrity of the affected systems but also poses a broader risk of malware propagation and further attacks within the network.

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