{"id":"USN-4698-2","aliases":[],"status":"published","title":"dnsmasq regression","description":"USN-4698-1 fixed vulnerabilities in Dnsmasq. The updates introduced\nregressions in certain environments related to issues with multiple\nqueries, and issues with retries. This update fixes the problem.\n\nOriginal advisory details:\n\n Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled\n memory when sorting RRsets. A remote attacker could use this issue to cause\n Dnsmasq to hang, resulting in a denial of service, or possibly execute\n arbitrary code. (CVE-2020-25681, CVE-2020-25687)\n \n Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled\n extracting certain names. A remote attacker could use this issue to cause\n Dnsmasq to hang, resulting in a denial of service, or possibly execute\n arbitrary code. (CVE-2020-25682, CVE-2020-25683)\n \n Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly\n implemented address/port checks. A remote attacker could use this issue to\n perform a cache poisoning attack. (CVE-2020-25684)\n \n Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly\n implemented query resource name checks. A remote attacker could use this\n issue to perform a cache poisoning attack. (CVE-2020-25685)\n \n Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled\n multiple query requests for the same resource name. A remote attacker could\n use this issue to perform a cache poisoning attack. (CVE-2020-25686)\n \n It was discovered that Dnsmasq incorrectly handled memory during DHCP\n response creation. A remote attacker could possibly use this issue to\n cause Dnsmasq to consume resources, leading to a denial of service. This\n issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04\n LTS. (CVE-2019-14834)","facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"published":"2021-02-24T13:43:44Z","modified":"2026-02-10T04:42:02Z","fixes":[{"ecosystem":"Ubuntu:16.04:LTS","package":"dnsmasq","fixed_in":["2.75-1ubuntu0.16.04.8"],"sources":["osv"]},{"ecosystem":"Ubuntu:18.04:LTS","package":"dnsmasq","fixed_in":["2.79-1ubuntu0.3"],"sources":["osv"]},{"ecosystem":"Ubuntu:20.04:LTS","package":"dnsmasq","fixed_in":["2.80-1.1ubuntu1.3"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"dnsmasq","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.75-1ubuntu0.16.04.8"}]}],"versions":["2.75-1","2.75-1ubuntu0.16.04.1","2.75-1ubuntu0.16.04.2","2.75-1ubuntu0.16.04.3","2.75-1ubuntu0.16.04.4","2.75-1ubuntu0.16.04.5","2.75-1ubuntu0.16.04.7"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"dnsmasq","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.79-1ubuntu0.3"}]}],"versions":["2.78-1","2.78-3","2.79-1","2.79-1ubuntu0.2"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"dnsmasq","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.80-1.1ubuntu1.3"}]}],"versions":["2.80-1ubuntu2","2.80-1ubuntu4","2.80-1.1ubuntu1","2.80-1.1ubuntu1.2"]}],"references":[{"url":"https://ubuntu.com/security/notices/USN-4698-2","tags":["advisory"]},{"url":"https://launchpad.net/bugs/1916462","tags":["report"]}],"sources":{"osv":[{"id":"USN-4698-2","title":"dnsmasq regression","description":"USN-4698-1 fixed vulnerabilities in Dnsmasq. The updates introduced\nregressions in certain environments related to issues with multiple\nqueries, and issues with retries. This update fixes the problem.\n\nOriginal advisory details:\n\n Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled\n memory when sorting RRsets. A remote attacker could use this issue to cause\n Dnsmasq to hang, resulting in a denial of service, or possibly execute\n arbitrary code. (CVE-2020-25681, CVE-2020-25687)\n \n Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled\n extracting certain names. A remote attacker could use this issue to cause\n Dnsmasq to hang, resulting in a denial of service, or possibly execute\n arbitrary code. (CVE-2020-25682, CVE-2020-25683)\n \n Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly\n implemented address/port checks. A remote attacker could use this issue to\n perform a cache poisoning attack. (CVE-2020-25684)\n \n Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly\n implemented query resource name checks. A remote attacker could use this\n issue to perform a cache poisoning attack. (CVE-2020-25685)\n \n Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled\n multiple query requests for the same resource name. A remote attacker could\n use this issue to perform a cache poisoning attack. (CVE-2020-25686)\n \n It was discovered that Dnsmasq incorrectly handled memory during DHCP\n response creation. A remote attacker could possibly use this issue to\n cause Dnsmasq to consume resources, leading to a denial of service. This\n issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04\n LTS. (CVE-2019-14834)\n","status":"published","published":"2021-02-24T13:43:44Z","modified":"2026-02-10T04:42:02Z","updated_at":"2026-11-02T16:58:15.159055Z"}]}}