What’s Vulnerable › Vulnerabilities
CVE-2026-27854: Use after free when parsing EDNS options in Lua
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.5% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-03-31 · updated 2026-07-25
- Weakness: CWE-416
Description
An attacker might be able to trigger a use-after-free by sending crafted DNS queries to a DNSdist using the DNSQuestion:getEDNSOptions method in custom Lua code. In some cases DNSQuestion:getEDNSOptions might refer to a version of the DNS packet that has been modified, thus triggering a use-after-free and potentially a crash resulting in denial of service.
Affected products
- PowerDNS DNSdist: from 1.9.0 before 1.9.12; from 2.0.0 before 2.0.3 — fixed in 1.9.12, 2.0.3
How to fix
Upgrade to a fixed version: PowerDNS DNSdist 1.9.12, 2.0.3. Check the vendor advisory for mitigations.
References
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