CVE-2019-6467 PoC — An error in the nxdomain redirect feature can cause BIND to exit with an INSIST assertion failure in query.c

Source

https://github.com/knqyf263/CVE-2019-6467

Associated Vulnerability

Title: An error in the nxdomain redirect feature can cause BIND to exit with an INSIST assertion failure in query.c (CVE-2019-6467)
Description:A programming error in the nxdomain-redirect feature can cause an assertion failure in query.c if the alternate namespace used by nxdomain-redirect is a descendant of a zone that is served locally. The most likely scenario where this might occur is if the server, in addition to performing NXDOMAIN redirection for recursive clients, is also serving a local copy of the root zone or using mirroring to provide the root zone, although other configurations are also possible. Versions affected: BIND 9.12.0-> 9.12.4, 9.14.0. Also affects all releases in the 9.13 development branch.

Description

CVE-2019-6467 (BIND nxdomain-redirect)

Readme

# CVE-2019-6467
BIND nxdomain-redirect

For educational purposes only

![demo](imgs/cve-2019-6467.gif)

## Run

```
$ docker run --rm --name cve-2019-6467 -it -p 53:53/udp knqyf263/cve-2019-6467
```

## Exploit
Normal query

```
$ dig @127.0.0.1 nxdomain.example.com
```

`nxdomain` can be replaced by anything that means non-existent domain name. (e.g. foobar.example.com)


## Reference
- https://ftp.isc.org/isc/bind/9.12.4-P1/RELEASE-NOTES-bind-9.12.4-P1.html
- https://ftp.isc.org/isc/bind9/9.14.1/RELEASE-NOTES-bind-9.14.1.html

File Snapshot

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