CVE-2020-8617

MEDIUM

Description

Using a specially-crafted message, an attacker may potentially cause a BIND server to reach an inconsistent state if the attacker knows (or successfully guesses) the name of a TSIG key used by the server. Since BIND, by default, configures a local session key even on servers whose configuration does not otherwise make use of it, almost all current BIND servers are vulnerable. In releases of BIND dating from March 2018 and after, an assertion check in tsig.c detects this inconsistent state and deliberately exits. Prior to the introduction of the check the server would continue operating in an inconsistent state, with potentially harmful results.

References

http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00041.html

http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00044.html

http://packetstormsecurity.com/files/157836/BIND-TSIG-Denial-Of-Service.html

http://www.openwall.com/lists/oss-security/2020/05/19/4

https://kb.isc.org/docs/cve-2020-8617

https://lists.debian.org/debian-lts-announce/2020/05/msg00031.html

https://lists.fedoraproject.org/archives/list/[email protected]/message/JKJXVBOKZ36ER3EUCR7VRB7WGHIIMPNJ/

https://lists.fedoraproject.org/archives/list/[email protected]/message/WOGCJS2XQ3SQNF4W6GLZ73LWZJ6ZZWZI/

https://security.netapp.com/advisory/ntap-20200522-0002/

https://usn.ubuntu.com/4365-1/

https://usn.ubuntu.com/4365-2/

https://www.debian.org/security/2020/dsa-4689

Details

Source: MITRE

Published: 2020-05-19

Updated: 2020-10-20

Type: CWE-617

Risk Information

CVSS v2.0

Base Score: 5

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P

Impact Score: 2.9

Exploitability Score: 10

Severity: MEDIUM

CVSS v3.0

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Impact Score: 3.6

Exploitability Score: 3.9

Severity: HIGH