A flaw was found in libcap. A local unprivileged user can exploit a Time-of-check-to-time-of-use (TOCTOU) race condition in the `cap_set_file()` function. This allows an attacker with write access to a parent directory to redirect file capability updates to an attacker-controlled file.
By doing so, capabilities can be injected into or stripped from unintended executables, leading to privilege escalation.
Attack Parameters
Attack Vector
Local
Requires local access
Attack Complexity
High
Difficult to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
Required
User action required
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v3.1
Weakness Type (CWE)
References 8
https://access.redhat.com/security/cve/CVE-2026-4878
secalert@redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2447554
secalert@redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2451615
secalert@redhat.com
http://www.openwall.com/lists/oss-security/2026/04/07/14
af854a3a-2127-422b-91ae-364da2661108
http://www.openwall.com/lists/oss-security/2026/04/07/4
af854a3a-2127-422b-91ae-364da2661108
http://www.openwall.com/lists/oss-security/2026/04/08/9
af854a3a-2127-422b-91ae-364da2661108
http://www.openwall.com/lists/oss-security/2026/04/09/5
af854a3a-2127-422b-91ae-364da2661108
http://www.openwall.com/lists/oss-security/2026/04/09/6
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