Vulnerability Report

CVE-2020-8617

Title: BIND Inconsistent State via TSIG key guessing

DoS

Proof Of Concept

PoC Available for CVE-2020-8617

CWE Category CWE-617
Published Date May 19, 2020
Modified Date Nov 21, 2024
Exploit Status Available
Score 7.5 CVSS v3.1
Exploit Probability (EPSS)
92.63%

Vulnerability Summary

CVE-2020-8617: 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.

Impacted Vendors

I
isc 1

Reference Links

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/package-announce%40lists.fedoraproject.org/message/JKJXVBOKZ36ER3EUCR7VRB7WGHIIMPNJ/ https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/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 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/package-announce%40lists.fedoraproject.org/message/JKJXVBOKZ36ER3EUCR7VRB7WGHIIMPNJ/ https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/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
CVSS v3.1
Source Entity [email protected]
Severity HIGH
7.5
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v3.1
Source Entity [email protected]
Severity MEDIUM
5.9
Attack Vector
NETWORK
Complexity
HIGH
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v2.0
Source Entity [email protected]
Severity MEDIUM
4.3
Access Vector
N/A
Authentication
N/A
RAW VECTOR AV:N/AC:M/Au:N/C:N/I:N/A:P

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2020-8617 Exploits & PoCs (Proof Of Concept)

Exploit-DB https://www.exploit-db.com/exploits/48521
View Code
MODIFIED

Vulnerability data or affected products updated.

PUBLISHED

Vulnerability first announced in NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity LOW
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected Stack

No specific products linked.