jakob@ and myself. See http://www.unbound.net/downloads/CVE-2011-4528.txt
for more details, summary from the above is below:
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Unbound crashes when confronted with a non-standard response from a
server for a domain. This domain produces duplicate RRs from a certain
type and is DNSSEC signed.Unbound also crashes when confronted with a
query that eventually, and under specific circumstances, resolves to a
domain that misses expected NSEC3 records.
These two problems were discovered within 24 hours, hence a combined
vulnerability disclosure.
By constructing the non standard responses an attacker can use these
vulnerabilities for a DOS attack.
To our knowledge 'denial of service' is the only type of exploit possible.
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