Ubuntu Security Notice 4698-2 - USN-4698-1 fixed vulnerabilities in Dnsmasq. The updates introduced regressions in certain environments related to issues with multiple queries, and issues with retries. This update fixes the problem. Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled memory when sorting RRsets. A remote attacker could use this issue to cause Dnsmasq to hang, resulting in a denial of service, or possibly execute arbitrary code. Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled extracting certain names. A remote attacker could use this issue to cause Dnsmasq to hang, resulting in a denial of service, or possibly execute arbitrary code. Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly implemented address/port checks. A remote attacker could use this issue to perform a cache poisoning attack. Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly implemented query resource name checks. A remote attacker could use this issue to perform a cache poisoning attack. Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled multiple query requests for the same resource name. A remote attacker could use this issue to perform a cache poisoning attack. It was discovered that Dnsmasq incorrectly handled memory during DHCP response creation. A remote attacker could possibly use this issue to cause Dnsmasq to consume resources, leading to a denial of service. This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. Various other issues were also addressed.
e42a5bdd054f191f80e2ffa56b1efcc9969c7a22e49b0f34c75af8093966adec