CVE-2026-27853: medium-severity vulnerability in PowerDNS DNSdist
Out-of-bounds write when rewriting large DNS packets
Published
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.9epss 0.5%
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 become larger than the initial response and even exceed 65535 bytes, potentially leading to a crash resulting in denial of service.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
PowerDNS · DNSdistRelated CVEs — PowerDNS DNSdist
In the same product, most dangerous first.
CVE-2025-30194HIGHDenial of service via crafted DoH exchangeEPSS 2.3%CVE-2024-25581HIGHTransfer requests received over DoH can lead to a denial of service in DNSdistEPSS 1.1%CVE-2026-33598MEDIUMOut-of-bounds read in cache inspection via LuaEPSS 1.1%CVE-2026-24028MEDIUMOut-of-bounds read when parsing DNS packets via LuaEPSS 1.1%CVE-2026-40210MEDIUMOut-of-bounds read in SetMacAddrActionEPSS 0.7%CVE-2026-33602MEDIUMOff-by-one access when processing crafted UDP responsesEPSS 0.7%