# HCSEC-2020-10 - Consul Server Crash With Invalid Service-Router Config Entry

**URL:** <https://discuss.hashicorp.com/t/hcsec-2020-10-consul-server-crash-with-invalid-service-router-config-entry/18093>\
**Category:** Security\
**Tags:** security-consul\
**Created:** [November 25, 2020, 7:29pm UTC](https://discuss.hashicorp.com/t/hcsec-2020-10-consul-server-crash-with-invalid-service-router-config-entry/18093 "2020-11-25T19:29:35Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![jfinnigan](https://sea2.discourse-cdn.com/hashicorp/user_avatar/discuss.hashicorp.com/jfinnigan/32/3834_2.png) [@jfinnigan](https://discuss.hashicorp.com/u/jfinnigan)\
**Post date:** [November 25, 2020, 7:29pm UTC](https://discuss.hashicorp.com/t/hcsec-2020-10-consul-server-crash-with-invalid-service-router-config-entry/18093/1 "2020-11-25T19:29:36Z")

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**Bulletin ID:** HCSEC-2020-10  
**Affected Products / Versions:** Consul and Consul Enterprise 1.6.0 - 1.6.5 and 1.7.0 - 1.7.3; fixed in 1.6.6 and 1.7.4.  
**Publication Date:** 10 June, 2020

**Summary**  
HashiCorp Consul and Consul Enterprise (“Consul”) could crash when configured with an abnormally-formed service-router entry. This vulnerability, CVE-2020-12758, was introduced in Consul 1.6.0 and fixed in 1.6.6 and 1.7.4.

**Background**  
Consul allows the definition of `service-router` ([documentation](https://www.consul.io/docs/agent/config-entries/service-router)) entries within the Consul configuration.

**Details**  
Introduced in Consul v1.6.0, a service-router config entry controls Connect traffic routing and manipulation at networking layer 7 (e.g. HTTP). When an entry is created without a destination, which requires an ACL token with `service:write` permissions, it is possible to crash Consul servers.

**Remediation**  
Customers should upgrade to Consul or Consul Enterprise 1.6.6 or 1.7.4, or newer. Please refer to [Upgrading Consul](https://www.consul.io/docs/upgrading.html) for general guidance and version-specific upgrade notes.

**Acknowledgement**  
This issue was identified by the HashiCorp engineering team.

_We deeply appreciate any effort to discover and disclose security vulnerabilities responsibly. For information about security at HashiCorp and the reporting of security vulnerabilities, please see [https://hashicorp.com/security](https://hashicorp.com/security)._