Short Name |
DNS:OVERFLOW:ADM-TCP |
---|---|
Severity |
Critical |
Recommended |
No |
Recommended Action |
Drop |
Category |
DNS |
Keywords |
ADM Buffer Overflow (TCP) |
Release Date |
2003/04/22 |
Update Number |
1213 |
Supported Platforms |
idp-4.0+, isg-3.0+, j-series-9.5+, mx-11.4+, srx-12.1+, srx-branch-12.1+, vmx-17.4+, vsrx-12.1+, vsrx3bsd-18.2+ |
This signature detects attempts to exploit a known vulnerability against NXT Bind. Attackers can cause a target nameserver to query TCP/53 on an attacker-controlled nameserver, where malicious data/code (built from t666.c) crafted to look like a NXT response is listening. When the query is made, the code executes and overruns the buffer that stores the NXT resource record response on the target nameserver. Attackers can gain root access.
There are several vulnerabilities in recent BIND packages (pre 8.2.2). The first is a buffer overflow condition which is a result of BIND improperly validating NXT records. The consequence of this being exploited is a remote root compromise (assuming that BIND is running as root, which is default). The second is a denial of service which can occur if BIND does not validate SIG records properly. The next is a bug which allows attackers to cause BIND to consume more file descriptors than can be managed, causing named to crash. The fourth vulnerability is another denial of service which can be caused locally if certain permission conditions are met when validating zone information loaded from disk files. The last is a vulnerability which has to do with closing TCP sockets. If protocols for doing so are not adhered to, BIND can be paused for 120 seconds at a time.