Executive brief
PowerDNS DNSdist, a popular tool for balancing and filtering DNS traffic, contains a flaw in its MAC address handling feature. An attacker could exploit this to cause the service to crash or to leak sensitive internal memory data over the network. This could lead to service interruptions or provide an attacker with information useful for further attacks.
Technical details
An out-of-bounds read vulnerability exists in PowerDNS DNSdist within the SetMacAddrAction component (specifically in dnsdist-actions-factory.cc). The flaw is triggered when SetMacAddrAction is used to process DNS queries, potentially leading to the transmission of uninitialized memory over the network or a process crash. The attack is network-reachable and requires no authentication, though it has high complexity as it depends on specific configuration and timing. The issue affects versions 1.9.x up to 1.9.14 and 2.0.x up to 2.0.6. It has been patched in versions 1.9.15 and 2.0.7.
Affected products
- PowerDNS DNSdist 1.9.0 to 1.9.14, 2.0.0 to 2.0.6
Timeline
- 2026-04-13: disclosed: Discovery date
- 2026-06-25: advisory: PowerDNS Security Advisory 2026-09 published
- 2026-06-25: patched: Fixed versions 1.9.15 and 2.0.7 released