Gentoo: GLSA-201001-05: net-snmp: Authorization bypass
Summary
The netsnmp_udp_fmtaddr() function (snmplib/snmpUDPDomain.c), when using TCP wrappers for client authorization, does not properly parse hosts.allow rules.
Resolution
All net-snmp users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=net-analyzer/net-snmp-5.4.2.1-r1"
References
[ 1 ] CVE-2008-6123 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2008-6123
Availability
This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:
https://security.gentoo.org/glsa/201001-05
Concerns
Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users machines is of utmost importance to us. Any security concerns should be addressed to security@gentoo.org or alternatively, you may file a bug at https://bugs.gentoo.org.
![Dist Gentoo](/images/distros/dist-gentoo.png)
Synopsis
A remote attacker can bypass the tcp-wrappers client authorization in net-snmp.
Background
net-snmp bundles software for generating and retrieving SNMP data.
Affected Packages
------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 net-analyzer/net-snmp < 5.4.2.1-r1 >= 5.4.2.1-r1
Impact
===== A remote, unauthenticated attacker could bypass the ACL filtering, possibly resulting in the execution of arbitrary SNMP queries.
Workaround
If possible, protect net-snmp with custom iptables rules:
iptables -s [client] -d [host] -p udp --dport 161 -j ACCEPT
iptables -s 0.0.0.0/0 -d [host] -p udp --dport 161 -j DROP