CVE-2020-8618: A buffer boundary check assertion in rdataset.c can fail incorrectly during zone transfer
  • 17 Jun 2020
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CVE-2020-8618: A buffer boundary check assertion in rdataset.c can fail incorrectly during zone transfer

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Article Summary

CVE: CVE-2020-8618

Document version: 2.0

Posting date: 17 June 2020

Program impacted: BIND

Versions affected: BIND 9.16.0 -> 9.16.3

Severity: Medium

Exploitable: Remotely

Description:

An assertion check in BIND (that is meant to prevent going beyond the end of a buffer when processing incoming data) can be incorrectly triggered by a large response during zone transfer.

Impact:

An attacker who is permitted to send zone data to a server via zone transfer can exploit this to intentionally trigger the assertion failure with a specially constructed zone, denying service to clients.

CVSS Score: 4.3

CVSS Vector: AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C

For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit: https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C&version=3.1.

Workarounds:

None

Active exploits:

We are not aware of any active exploits.

Solution:

Upgrade to the patched release most closely related to your current version of BIND:

  • BIND 9.16.4

Document revision history:

1.0 Early Notification, 10 June 2020
1.1 Simplified "Exploitable" section, 17 June 2020
2.0 Public disclosure, 17 June 2020

Related documents:

See our BIND 9 Security Vulnerability Matrix for a complete listing of security vulnerabilities and versions affected.

Do you still have questions? Questions regarding this advisory should go to security-officer@isc.org. To report a new issue, please encrypt your message using security-officer@isc.org's PGP key which can be found here: https://www.isc.org/pgpkey/. If you are unable to use encrypted email, you may also report new issues at: https://www.isc.org/reportbug/.

Note:

ISC patches only currently supported versions. When possible we indicate EOL versions affected. (For current information on which versions are actively supported, please see https://www.isc.org/download/.)

ISC Security Vulnerability Disclosure Policy:

Details of our current security advisory policy and practice can be found in the ISC Software Defect and Security Vulnerability Disclosure Policy at https://kb.isc.org/docs/aa-00861.

The Knowledgebase article https://kb.isc.org/docs/cve-2020-8618 is the complete and official security advisory document.

Legal Disclaimer:

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