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CVE-2026-50243 on CTRL-OS 26.05

Aliases: CVE-2026-50243

Packages: unbound

Status: In Progress

Advisory Information

In NLnet Labs Unbound 1.6.2 up to and including 1.25.1, when Unbound is configured with the 'respip' module in front of the validator together with a 'response-ip' redirect rule or an RPZ file with an RPZ-IP trigger, the rewriting handler does not check the security status of the upstream answer and can instead rewrite a BOGUS A/AAAA answer to point to an operator's configured IP. If the validator finds an expired or otherwise invalid RRSIG on an answer whose A record falls within a 'response-ip'/RPZ configuration, the answer is still rewritten and given a hard coded security level of INSECURE. This results in the client receiving an INSECURE NOERROR reply rewritten by the operator's configured IP. A malicious actor can exploit the possible poisonous effect by spoofing a BOGUS A/AAAA answer that falls inside the operator's configured subnet rewrites. Such DNSSEC protected answers are then insecurely redirected to the operator's configured target.

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”