{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/tags/cve-2026-3039/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[{"cvss":7.5,"id":"CVE-2026-3039"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["BIND 9"],"_cs_severities":["medium"],"_cs_tags":["cve","cve-2026-3039","bind9","denial-of-service","memory-consumption"],"_cs_type":"advisory","_cs_vendors":["ISC"],"content_html":"\u003cp\u003eISC BIND 9 is vulnerable to excessive memory consumption (CVE-2026-3039) when processing maliciously crafted packets targeting servers using TKEY-based authentication via GSS-API tokens. This configuration is often found in Active Directory-integrated DNS deployments or Kerberos-secured DNS environments. An attacker can exploit this vulnerability by sending specially crafted packets, causing the BIND server to consume excessive memory resources, potentially leading to denial of service. The affected versions include BIND 9 versions 9.0.0 through 9.16.50, 9.18.0 through 9.18.48, 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, 9.9.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.48-S1, and 9.20.9-S1 through 9.20.22-S1. Defenders should monitor DNS server memory usage and implement rate limiting or packet filtering to mitigate the risk.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eThe attacker identifies a BIND server configured to use TKEY-based authentication with GSS-API.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a malicious DNS packet specifically designed to exploit the memory consumption vulnerability.\u003c/li\u003e\n\u003cli\u003eThe attacker sends the crafted packet to the vulnerable BIND server.\u003c/li\u003e\n\u003cli\u003eThe BIND server receives the packet and attempts to process the TKEY authentication.\u003c/li\u003e\n\u003cli\u003eDue to the malicious structure of the packet, the server allocates an excessive amount of memory during the authentication process.\u003c/li\u003e\n\u003cli\u003eThe attacker repeats steps 3-5, sending multiple crafted packets to continually exhaust server memory.\u003c/li\u003e\n\u003cli\u003eThe BIND server\u0026rsquo;s memory consumption increases significantly, impacting performance and stability.\u003c/li\u003e\n\u003cli\u003eThe BIND server eventually crashes due to memory exhaustion, resulting in a denial-of-service condition.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-3039 leads to excessive memory consumption on the affected BIND server, potentially resulting in a denial-of-service condition. This can disrupt DNS resolution services for the affected domain or network, impacting users\u0026rsquo; ability to access websites and online services. The vulnerability poses a significant risk to organizations relying on Active Directory-integrated DNS or Kerberos-secured DNS environments, potentially causing widespread service outages.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUpgrade BIND 9 to a patched version beyond 9.16.50, 9.18.48, 9.20.22, or 9.21.21 to remediate CVE-2026-3039.\u003c/li\u003e\n\u003cli\u003eImplement rate limiting on DNS traffic to mitigate the impact of malicious packets, protecting against memory exhaustion.\u003c/li\u003e\n\u003cli\u003eMonitor DNS server memory usage for unexpected spikes using system monitoring tools.\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule \u003ccode\u003eDetect Excessive DNS Server Memory Allocation\u003c/code\u003e to identify potential exploitation attempts.\u003c/li\u003e\n\u003cli\u003eReview DNS server configurations to minimize the use of TKEY-based authentication where possible.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-05-20T13:22:34Z","date_published":"2026-05-20T13:22:34Z","id":"https://feed.craftedsignal.io/briefs/2026-05-cve-2026-3039-bind-memory-consumption/","summary":"BIND servers configured for TKEY-based authentication using GSS-API tokens are susceptible to excessive memory consumption upon receiving and processing crafted packets, impacting availability.","title":"CVE-2026-3039: BIND TKEY Authentication Memory Consumption Vulnerability","url":"https://feed.craftedsignal.io/briefs/2026-05-cve-2026-3039-bind-memory-consumption/"}],"language":"en","title":"CraftedSignal Threat Feed — Cve-2026-3039","version":"https://jsonfeed.org/version/1.1"}