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CVE-2026-44621 on CTRL-OS 26.05

Aliases: CVE-2026-44621

Packages: unbound

Status: In Progress

Advisory Information

With NLnet Labs Unbound up to and including version 1.25.1, applications using libunbound and configured with 'unwanted-reply-threshold', could eventually be abruptly terminated if the threshold is reached and libunbound needs to call 'libworker_alloc_cleanup' since the function is absent from the function call allow list. When an application using libunbound sets 'unwanted-reply-threshold' to any non-zero value and the iterator queries an authoritative that replies with enough wrong-transaction-ID UDP datagrams to cross the threshold, the 'libworker_alloc_cleanup' will eventually be called. Since the function is absent from the function call allow list, this leads to a fatal exit of libunbound and eventual termination of the embedding application.Unbound itself is not affected since its relevant function 'worker_alloc_cleanup' is registed in the allow list and proceeds to perform the documented cache flush.

Updates

2026-07-27 19:41 CEST

Metadata changes:

  • Status for package unbound: “In Progress” (6adb4107d901bc4e75e7e4659d2eccdaebe38c21)

2026-07-23 23:53 CEST

Metadata changes:

  • Status for package unbound: “Plausible”

2026-07-23 23:53 CEST

Metadata changes:

  • Status for package unbound: “New”