Ubuntu 20.04: Bind Important Denial of Service Cache Poisoning USN-7836-2

A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 20.04 LTS Summary: Several security issues were fixed in Bind. Software Description: - bind9: Internet Domain Name Server Details: USN-7836-1 fixed vulnerabilities in Bind. This update provides the corresponding fixes for Ubuntu 20.04 LTS. Original advisory details: Zuyao Xu and Xiang Li discovered that Bind incorrectly handled certain malformed DNSKEY records. A remote attacker could possibly use this issue to cause Bind to consume resources, resulting in a denial of service. (CVE-2025-8677) Yuxiao Wu, Yunyi Zhang, Baojun Liu, and Haixin Duan discovered that Bind incorrectly accepted certain records from answers. A remote attacker could possibly use this issue to perform a cache poisoning attack. (CVE-2025-40778) Amit Klein and Omer Ben Simhon discovered that Bind used a weak PRNG. A remote attacker could possibly use this issue to perform a cache poisoning attack. (CVE-2025-40780)