CVE-2026-109969

A flaw was found in the clevis PKCS#11 pin. The clevis-pkcs11-afunix-socket-unlock daemon creates AF_UNIX sockets without explicit permission restrictions or peer credential verification. Under a permissive process umask, any local user can connect to the control socket and inject arbitrary device/key pairs, or connect to the data socket to receive LUKS passphrases.

The PKCS#11 clevis pin is an opt-in feature requiring explicit configuration (clevis luks bind pkcs11), PKCS#11 hardware, and activation of the corresponding systemd service or dracut module. Default clevis installations are not affected.

Red Hat rates this Moderate because under the default systemd UMask of 0022, sockets are created with mode 0755. AF_UNIX SOCK_STREAM requires write permission to connect, so unprivileged users cannot connect in the default configuration. The vulnerability is exploitable only when the process umask is permissive (e.g., in certain dracut initramfs configurations) or when the umask is explicitly set to 0000.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Configure the clevis-luks-pkcs11-askpass systemd service with a restrictive UMask by creating a service override using systemctl edit. Setting UMask to 0077 ensures the sockets are only accessible by root, preventing unauthorized connections.

This workaround only covers the systemd service path. The dracut initramfs code path is not covered by this mitigation.