Debian corosync DoS Advisory DLA-4608-1 CVE-2026-35091 CVE-2026-35092

Two vulnerabilities have been found in corosync, a cluster engine daemon and
utilities, that allow a remote, unauthenticated attacker to cause a denial of
service.

CVE-2026-35091

A remote unauthenticated attacker can exploit a wrong return value
vulnerability in the Corosync membership commit token sanity check by
sending a specially crafted User Datagram Protocol (UDP) packet. This can
lead to an out-of-bounds read, causing a denial of service (DoS) and
potentially disclosing limited memory contents.

CVE-2026-35092

An integer overflow vulnerability in Corosync's join message sanity
validation allows a remote, unauthenticated attacker to send crafted User
Datagram Protocol (UDP) packets. This can cause the service to crash,
leading to a denial of service.

For Debian 11 bullseye, these problems have been fixed in version
3.1.2-2+deb11u2.

We recommend that you upgrade your corosync packages.

For the detailed security status of corosync please refer to