What is the CVSS score of CVE-2020-8617?

CVE-2020-8617 has a CVSS 3.1 base score of 5.9 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 93.4%.

Is there a public PoC exploit available for CVE-2020-8617?

Yes, a public proof-of-concept exploit is available for CVE-2020-8617. Prioritise patching immediately. EPSS: 93.4%.

Is there a patch available for CVE-2020-8617?

Yes, a patch is available for CVE-2020-8617. Update the affected software to the latest version immediately.

Bind CVE-2020-8617

MEDIUM

Reachable Assertion (CWE-617)

2020-05-19 security-officer@isc.org

Denial Of Service Bind Debian Linux Fedora Leap Ubuntu Linux

5.9

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

5.9 MEDIUM

AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

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

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

CVE Published

May 19, 2020 - 14:15 nvd

MEDIUM 5.9

DescriptionNVD

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.

AnalysisAI

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. Rated medium severity (CVSS 5.9), this vulnerability is remotely exploitable, no authentication required. Public exploit code available.

Technical ContextAI

This vulnerability is classified under CWE-617. 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. Affected products include: Isc Bind, Debian Debian Linux, Fedoraproject Fedora, Opensuse Leap, Canonical Ubuntu Linux.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.