From: Michał Kępień <michal@isc.org>
Date: Fri, 13 Mar 2026 12:16:28 +0000 (+0100)
Subject: [CVE-2026-1519] sec: usr: Fix unbounded NSEC3 iterations when validating referrals... 
X-Git-Tag: v9.21.20~5
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=779463a703e109d2f65e9a09745bfebd2b9d4164;p=thirdparty%2Fbind9.git

[CVE-2026-1519] sec: usr: Fix unbounded NSEC3 iterations when validating referrals to unsigned delegations

DNSSEC-signed zones may contain high iteration-count NSEC3 records,
which prove that certain delegations are insecure. Previously, a
validating resolver encountering such a delegation processed these
iterations up to the number given, which could be a maximum of 65,535.
This has been addressed by introducing a processing limit, set at 50.
Now, if such an NSEC3 record is encountered, the delegation will be
treated as insecure.

ISC would like to thank Samy Medjahed/Ap4sh for bringing this
vulnerability to our attention.

Closes isc-projects/bind9#5708

Merge branch '5708-confidential-nsec3-delegation-iteration-fix-fallback-to-insecure' into 'v9.21.20-release'

See merge request isc-private/bind9!935
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779463a703e109d2f65e9a09745bfebd2b9d4164