Vitaly Simonovich discovered that Bind could exhaust memory during GSS-API TKEY negotiation. A remote attacker could possibly use this issue to cause Bind to use excessive resources, leading to a denial of service. (CVE-2026-3039) Shuhan Zhang discovered that Bind incorrectly handled self-pointed glue records. A remote attacker could possibly use this issue to use Bind in denial of service amplification attacks against other systems. (CVE-2026-3592) Naresh Kandula Parmar discovered that Bind incorrectly handled memory in the DNS-over-HTTPS implementation. A remote attacker could possibly use this issue to cause Bind to crash, resulting in a denial of service, or execute arbitrary code. This issue only affected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-3593) It was discovered that Bind incorrectly handled DNS messages whose class was not IN. A remote attacker could possibly use this issue to cause Bind to crash, resulting in a denial of service. (CVE-2026-5946) Naoki Wakamatsu discovered that Bind incorrectly handled SIG(0) validation during a query flood. A remote attacker could possibly use this issue to cause Bind to crash, resulting in a denial of service. This issue only affected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-5947) Billy Baraja discovered that Bind had an unbounded resend loop in the resolver. A remote attacker could possibly use this issue to cause Bind to use excessive resources, leading to a denial of service. (CVE-2026-5950)
Multiple vulnerabilities in ISC BIND allow remote attackers to cause denial of service via resource exhaustion or crashes; specific issues include memory exhaustion during GSS-API TKEY negotiation (CVE-2026-3039, CVSS 7.5), mishandling of self-pointed glue records enabling amplification attacks (CVE-2026-3592, CVSS 5.3), and memory corruption in the DNS-over-HTTPS implementation potentially leading to RCE (CVE-2026-3593, CVSS 7.4). Affected versions include BIND 9.18.0 to 9.18.48, 9.20.0 to 9.20.22, and 9.21.0 to 9.21.21. These are fixed in BIND versions 9.18.49, 9.20.23, and 9.21.22 respectively.