/ 
Net-DNS-0.10
/ Net::DNS::RR
Security Advisories (5)
CVE-2007-6341 (2008-02-08)

Allows remote attackers to cause a denial of service (program "croak") via a crafted DNS response.

CVE-2007-3409 (2007-06-26)

Net::DNS before 0.60, a Perl module, allows remote attackers to cause a denial of service (stack consumption) via a malformed compressed DNS packet with self-referencing pointers, which triggers an infinite loop.

CVE-2007-3377 (2007-06-25)

Header.pm in Net::DNS before 0.60, a Perl module, (1) generates predictable sequence IDs with a fixed increment and (2) can use the same starting ID for all child processes of a forking server, which allows remote attackers to spoof DNS responses, as originally reported for qpsmtp and spamassassin.

CVE-2026-64193 (2026-07-20)

Net::DNS versions through 1.55 for Perl allow remote execution injection via EDNS EXTENDED ERROR. Net::DNS::RR::OPT::EXTENDED_ERROR::_decompose parses the EXTRA-TEXT field of an EDNS EXTENDED-ERROR option (RFC 8914) by tokenising the raw bytes and passing the result to Perl's eval. There is some escaping done for $ and @, but not for backticks. This can be exploited for command execution if $pkt->edns->option('EXTENDED-ERROR') is called in array context, for example with a payload of {0:`"<command>"`} in EXTRA-TEXT.

CVE-2026-64194 (2026-07-20)

Net::DNS versions through 1.55 for Perl allow Denial of Service via deep DNS compression pointer chains. Net::DNS::DomainName::decode follows RFC 1035 compression pointers by recursing into itself with no depth limit. It is possible to construct a name which saturates the call stack (at least with larger TCP responses), leading to a potential Denial of Service. The guard `$link < $offset` prevents forward and circular chains, but still allows arbitrarily long backward chains. The per-offset cache (`$cache`) is populated at the start of each call and short-circuits only re-traverses of the same offset - the initial descent through a fresh chain still recurses at full depth. A crafted packet can chain two-byte compression pointers so that each one points two bytes earlier than the previous, producing a chain length of `offset / 2`. For the 14-bit pointer field (max offset 16383) this gives up to ~8191 recursive frames. For a TCP DNS message the limit is the 16-bit length field (~32767 frames). Perl's default C stack handles only a few thousand frames; beyond that the process receives SIGSEGV or similar, which is a denial-of-service for any application parsing untrusted DNS data. The vulnerability is triggered by `Net::DNS::Packet->new(\$wire)` i.e. any point where the library decodes a DNS message from the network.

NAME

Net::DNS::RR - DNS Resource Record class

SYNOPSIS

use Net::DNS::RR

DESCRIPTION

Net::DNS::RR is the base class for DNS Resource Record (RR) objects. See also the manual pages for each RR type.

METHODS

new

    $rr = new Net::DNS::RR(
	Name    => "foo.bar.com",
	TTL     => 86400,
	Class   => "IN",
        Type    => "A",
	Address => "10.1.2.3",
    );

    $rr = new Net::DNS::RR(
	Name    => "foo.bar.com",
        Type    => "A",
    );

Returns an RR object of the appropriate type, or a Net::DNS::RR object if the type isn't implemented. See the manual pages for each RR type to see what fields the type requires.

The Name and Type fields are required; all others are optional. If omitted, TTL defaults to 0 and Class defaults to IN. Omitting the optional fields is useful for creating the empty RDATA sections required for certain dynamic update operations.

The fields are case-insensitive, but starting each with uppercase is recommended.

print

$rrobj->print;

Prints the record to the standard output. Calls the string method to get the RR's string representation.

string

print $rrobj->string, "\n";

Returns a string representation of the RR. Calls the rdatastr method to get the RR-specific data.

rdatastr

$s = $rrobj->rdatastr;

Returns a string containing RR-specific data. Subclasses will need to implement this method.

name

$name = $rrobj->name;

Returns the record's domain name.

type

$type = $rrobj->type;

Returns the record's type.

class

$class = $rrobj->class;

Returns the record's class.

ttl

$ttl = $rrobj->ttl;

Returns the record's time-to-live (TTL).

rdlength

$rdlength = $rrobj->rdlength;

Returns the length of the record's data section.

rdata

$rdata = $rrobj->rdata

Returns the record's data section as binary data.

BUGS

This version of Net::DNS::RR does no sanity checking on user-created RR objects.

COPYRIGHT

Copyright (c) 1997 Michael Fuhr. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

SEE ALSO

perl(1), Net::DNS, Net::DNS::Resolver, Net::DNS::Packet, Net::DNS::Update, Net::DNS::Header, Net::DNS::Question, RFC 1035 Section 4.1.3