{"id":"CVE-2026-27853","title":"An attacker might be able to trigger an out-of-bounds write by sending crafted DNS responses to a DNSdist using the DNSQuestion:changeName or DNSResponse:changeName methods in custom Lua code","summary":"An attacker might be able to trigger an out-of-bounds write by sending crafted DNS responses to a DNSdist using the DNSQuestion:changeName or DNSResponse:changeName methods in custom Lua code. In some cases the rewritten packet might bec…","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-787"],"vendor":"powerdns","product":"dnsdist","affected":["dnsdist >= 1.9.0, < 1.9.12","dnsdist >= 2.0.0, < 2.0.3"],"patched":["dnsdist 2.0.3"],"published":"2026-03-31","updated":"2026-07-25","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-27853","references":[{"url":"https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-02.html","label":"security@open-xchange.com"}],"tags":["nvd"],"epss":0.00489,"epssPercentile":0.41223,"ingestedAt":"2026-07-25T10:53:53.250Z","slug":"CVE-2026-27853","body":"## Overview\n\nAn attacker might be able to trigger an out-of-bounds write by sending crafted DNS responses to a DNSdist using the DNSQuestion:changeName or DNSResponse:changeName methods in custom Lua code. In some cases the rewritten packet might become larger than the initial response and even exceed 65535 bytes, potentially leading to a crash resulting in denial of service.\n\n## Affected\n\n- `dnsdist >= 1.9.0, < 1.9.12`\n- `dnsdist >= 2.0.0, < 2.0.3`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `dnsdist 2.0.3`","depth":"sunlit","depthScore":33,"depthScoreParts":{"impact":32.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}