Bug 1770713 (CVE-2019-18836)

Summary: CVE-2019-18836 envoy: excessive iteration due to listener filter timeout leads to DoS
Product: [Other] Security Response Reporter: Marian Rehak <mrehak>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED NOTABUG QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: kconner, rcernich, twalsh
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: envoy 1.12.1 Doc Type: If docs needed, set a value
Doc Text:
A flaw was found in envoy. When listeners are configured with `continue_on_listener_filters_timeout` true, an infinite busy loop is created if at least one connection is maintained on the loop. A remote attacker only needs to maintain one idle connection to consume one CPU core of the Envoy server, potentially leading to a denial of service attack. The highest threat from this vulnerability is to system availability.
 Story Points: ---
Clone Of: Environment:
Last Closed: 2019-11-26 13:04:53 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 1773455    

Description Marian Rehak 2019-11-11 08:49:48 UTC 
An attacker can create a TCP connection to listeners configured with `continue_on_listener_filters_timeout` true, wait for Envoy hitting the listener timeout and burn 1 core for the worker thread.
Comment 1 Marian Rehak 2019-11-11 08:50:27 UTC 
Upstream issue:

https://github.com/envoyproxy/envoy/security/advisories/GHSA-3xvf-4396-cj46

Upstream Fix:

https://github.com/envoyproxy/envoy/commit/c8de199e2971f79cbcbc6b5eadc8c566b28705d1
Comment 2 Marian Rehak 2019-11-11 08:51:49 UTC 
This issue doesn't affect Envoy versions < 1.12.0.
Comment 3 Product Security DevOps Team 2019-11-26 13:04:53 UTC 
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2019-18836
Comment 4 Eric Christensen 2020-05-05 13:44:15 UTC 
External References:

https://github.com/envoyproxy/envoy/security/advisories/GHSA-3xvf-4396-cj46