FreeBSD has released a VuXML document and updated ports collection to address the ISC BIND malformed zone request processing denial of service vulnerability.
A vulnerability in the ISC BIND server could cause an unauthenticated, remote attacker to cause a denial of service (DoS) condition.
The vulnerability exists because the recursive resolver component incorrectly processes recursive queries for a malformed zone. An unauthenticated, remote attacker could exploit the vulnerability by transmitting a crafted resolution query for a malformed zone. A successful attack could allow the attacker to cause a DoS condition on the targeted system.
ISC has confirmed the vulnerability and released software updates.
ISC BIND versions 9.6-ESV-R9, 9.8.5, and 9.9.3 are vulnerable.
To exploit the vulnerability the attacker may need access to trusted or internal networks to be able to transmit DNS queries to targeted servers. This access requirement could limit the likelihood of a successful attack.
Vendor reports that ISC BIND versions 9.6.0 through 9.6-ESV-R8, 9.8.0 through 9.8.4-P2, and 9.9.0 through 9.9.2-P2 are not affected.
ISC has released a security notice at the following link: CVE-2013-3919
An unauthenticated, remote attacker could exploit the vulnerability to crash the named daemon service triggering a RUNTIME_CHECK error . This may cause a DoS condition for legitimate DNS client users.
The vulnerability exists in the resolver.c source file of an affected recursive resolver implementation of a BIND server. When processing a resolution query for a certain zone, the resolver could perform recursive resolution to higher domains and could cause the named daemon service to terminate unexpectedly if the query record is not available with the authoritative servers.
An unauthenticated, remote attacker could exploit the vulnerability by transmitting a resolution query for a malformed zone. This could cause the server to stop responding to legitimate DNS client users.
Administrators are advised to apply the appropriate updates.
Administrators are advised to only allow trusted users to have network access.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems.
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