Knot Resolver 6.5.1 released

Thursday, October 22, 2026

Security

  • fix crash when forwarding - DoS via NULL deref Reporters: Yuqi Qiu and Xiang Li, Nankai University (AOSP Lab).
  • fix crash or loop - DoS Reporters: Joshua from AISLE
  • exhaustion of ports for outgoing TCP - DoS The attack only worked if /network/out-interface-* was configured. Reporters: Jonathan Horovitz, Yehuda Afek, and Anat Bremler-Barr from Tel Aviv University.

Bugfixes

  • python: fix logging level mapping bug, regressed in 6.5.0 (!1918)
  • fix build with musl libc, regressed in 6.5.0 (!1917)
  • DoH: the unencrypted mode opened also a UDP socket (!1921)

Improvements

  • performance of reloads with large cache on tmpfs (!1924)