Back Linuxsecurity Ubuntu 25.10 Corosync Faces Critical DoS Vulnerability 2026
A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 25.10 - Ubuntu 24.04 LTS - Ubuntu 22.04 LTS Summary: Several security issues were fixed in Corosync. Software Description: - corosync: cluster engine daemon and utilities Details: It was discovered that Corosync incorrectly handled the membership commit token validity check. A remote attacker could use this issue to cause Corosync to crash, resulting in a denial of service, or to possibly obtain a small quantity of sensitive information. (CVE-2026-35091) It was discovered that Corosync incorrectly handled join message validation. A remote attacker could possibly use this issue to cause Corosync to crash, resulting in a denial of service. (CVE-2026-35092)
A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 25.10 - Ubuntu 24.04 LTS - Ubuntu 22.04 LTS Summary: Several security issues were fixed in Corosync. Software Description: - corosync: cluster engine daemon and utilities Details: It was discovered that Corosync incorrectly handled the membership commit token validity check. A remote attacker could use this issue to cause Corosync to crash, resulting in a denial of service, or to possibly obtain a small quantity of sensitive information. (CVE-2026-35091) It was discovered that Corosync incorrectly handled join message validation. A remote attacker could possibly use this issue to cause Corosync to crash, resulting in a denial of service. (CVE-2026-35092)
The problem can be corrected by updating your system to the following package versions: Ubuntu 25.10 corosync 3.1.9-2ubuntu1.1 Ubuntu 24.04 LTS corosync 3.1.7-1ubuntu3.2 Ubuntu 22.04 LTS corosync 3.1.6-1ubuntu1.2 After a standard system update you need to restart Corosync to make all the necessary changes.
The problem can be corrected by updating your system to the following package versions: Ubuntu 25.10 corosync 3.1.9-2ubuntu1.1 Ubuntu 24.04 LTS corosync 3.1.7-1ubuntu3.2 Ubuntu 22.04 LTS corosync 3.1.6-1ubuntu1.2 After a standard system update you need to restart Corosync to make all the necessary changes.
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