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>1.6. PowerDNS Security Advisory 2006-02: Zero second CNAME TTLs can make PowerDNS exhaust allocated stack space, and crash</A
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>Table 1-2. PowerDNS Security Advisory</B
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><TD
> CVE
</TD
><TD
> CVE-2006-4252
</TD
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><TR
><TD
> Date
</TD
><TD
> 13th of November 2006
</TD
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><TR
><TD
> Affects
</TD
><TD
> PowerDNS Recursor versions 3.1.3 and earlier, on all operating systems.
</TD
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><TD
> Not affected
</TD
><TD
> No versions of the PowerDNS Authoritative Server ('pdns_server') are affected.
</TD
></TR
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><TD
> Severity
</TD
><TD
> Moderate
</TD
></TR
><TR
><TD
> Impact
</TD
><TD
> Denial of service
</TD
></TR
><TR
><TD
> Exploit
</TD
><TD
> This problem can be triggered by sending queries for specifically configured domains
</TD
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><TD
> Solution
</TD
><TD
> Upgrade to PowerDNS Recursor 3.1.4, or apply <A
HREF="http://wiki.powerdns.com/projects/trac/changeset/919"
TARGET="_top"
>commit 919</A
>.
</TD
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><TD
> Workaround
</TD
><TD
> None known. Exposure can be limited by configuring the <B
CLASS="COMMAND"
>allow-from</B
> setting so only trusted users
can query your nameserver.
</TD
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> PowerDNS would recurse endlessly on encountering a CNAME loop consisting entirely of zero second CNAME records, eventually exceeding resources and crashing.
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