BIND 8.3.x through 8.3.3 allows remote attackers to cause a denial of service (termination due to assertion failure) via a request for a subdomain that does not exist, with an OPT resource record with a large UDP payload size.

[Bind version 9, the bind9 package, is not affected by these problems.]

ISS X-Force has discovered several serious vulnerabilities in the Berkeley Internet Name Domain Server (BIND). BIND is the most common implementation of the DNS (Domain Name Service) protocol, which is used on the vast majority of DNS servers on the Internet. DNS is a vital Internet protocol that maintains a database of easy-to-remember domain names (host names) and their corresponding numerical IP addresses.

Circumstantial evidence suggests that the Internet Software Consortium (ISC), maintainers of BIND, was made aware of these issues in mid-October. Distributors of Open Source operating systems, including Debian, were notified of these vulnerabilities via CERT about 12 hours before the release of the advisories on November 12th. This notification did not include any details that allowed us to identify the vulnerable code, much less prepare timely fixes.

Unfortunately ISS and the ISC released their security advisories with only descriptions of the vulnerabilities, without any patches. Even though there were no signs that these exploits are known to the black-hat community, and there were no reports of active attacks, such attacks could have been developed in the meantime - with no fixes available.

We can all express our regret at the inability of the ironically named Internet Software Consortium to work with the Internet community in handling this problem. Hopefully this will not become a model for dealing with security issues in the future.

The Common Vulnerabilities and Exposures (CVE) project identified the following vulnerabilities :

  - CAN-2002-1219: A buffer overflow in BIND 8 versions     8.3.3 and earlier allows a remote attacker to execute     arbitrary code via a certain DNS server response     containing SIG resource records (RR). This buffer     overflow can be exploited to obtain access to the victim     host under the account the named process is running     with, usually root.
  - CAN-2002-1220: BIND 8 versions 8.3.x through 8.3.3     allows a remote attacker to cause a denial of service     (termination due to assertion failure) via a request for     a subdomain that does not exist, with an OPT resource     record with a large UDP payload size.

  - CAN-2002-1221: BIND 8 versions 8.x through 8.3.3 allows     a remote attacker to cause a denial of service (crash)     via SIG RR elements with invalid expiry times, which are     removed from the internal BIND database and later cause     a null dereference.

These problems have been fixed in version 8.3.3-2.0woody1 for the current stable distribution (woody), in version 8.2.3-0.potato.3 for the previous stable distribution (potato) and in version 8.3.3-3 for the unstable distribution (sid). The fixed packages for unstable will enter the archive today.

The remote BIND server is vulnerable to three different vulnerabilities : 
1) The remote BIND server, based on its version number, if running recursive DNS functionality, is vulnerable to a buffer overflow.
2) The remote BIND server is vulnerable to a denial of service (crash) via SIG RR elements with invalid expiry times.
3) The remote BIND server is vulnerable to a denial of service.
When a DNS lookup is requested on a non-existant sub-domain of a valid domain and an OPT resource record with a large UDP payload is attached, the server may fail.   

The remote name server, according to its version number, is affected by the following vulnerabilities :

- When running the recursive DNS functionality, this server is vulnerable to a buffer overflow attack that may let an attacker execute arbitrary code on the remote host. 

- It is vulnerable to a denial of service attack (crash) via SIG RR elements with invalid expiry times. 

- It is vulnerable to a denial of service attack when a DNS lookup is requested on a nonexistent sub-domain of a valid domain and an OPT resource record with a large UDP payload is attached, the server may fail.

ID	Name	Product	Family	Type	Severity
15033	Debian DSA-196-1 : bind - several vulnerabilities	Nessus	Debian Local Security Checks	Local	high
1006	ISC BIND < 8.3.4 Multiple Remote Vulnerabilities (deprecated)	Nessus Network Monitor	DNS Servers		high
10886	ISC BIND < 8.3.4 Multiple Remote Vulnerabilities	Nessus	DNS	Remote	high

Detections

Analytics

CVE-2002-1220

high

Tenable Plugins

high

high

high