Back Linuxsecurity Ubuntu 25.10 Policykit Important Denial of Service Issues USN-8173
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 polkit. Software Description: - policykit-1: framework for managing administrative policies and privileges Details: It was discovered that polkit incorrectly handled nested elements in XML policy files. If an administrator were tricked into installing a malicious policy file, a remote attacker could possibly use this issue to cause polkit to crash, resulting in a denial of service. (CVE-2025-7519) Pavel Kohout discovered that the polkit polkit-agent-helper-1 utility incorrectly handled long input. A local attacker could possibly use this issue to cause polkit to crash, resulting in a denial of service. (CVE-2026-4897)
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 polkit. Software Description: - policykit-1: framework for managing administrative policies and privileges Details: It was discovered that polkit incorrectly handled nested elements in XML policy files. If an administrator were tricked into installing a malicious policy file, a remote attacker could possibly use this issue to cause polkit to crash, resulting in a denial of service. (CVE-2025-7519) Pavel Kohout discovered that the polkit polkit-agent-helper-1 utility incorrectly handled long input. A local attacker could possibly use this issue to cause polkit to crash, resulting in a denial of service. (CVE-2026-4897)
The problem can be corrected by updating your system to the following package versions: Ubuntu 25.10 polkitd 126-2ubuntu0.1 Ubuntu 24.04 LTS policykit-1 124-2ubuntu1.24.04.3 Ubuntu 22.04 LTS policykit-1 0.105-33ubuntu0.1 In general, a standard system update will make all the necessary changes.
The problem can be corrected by updating your system to the following package versions: Ubuntu 25.10 polkitd 126-2ubuntu0.1 Ubuntu 24.04 LTS policykit-1 124-2ubuntu1.24.04.3 Ubuntu 22.04 LTS policykit-1 0.105-33ubuntu0.1 In general, a standard system update will make all the necessary changes.
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