Bug 1964874 (CVE-2021-29509)

Summary:	CVE-2021-29509 rubygem-puma: incomplete fix for CVE-2019-16770 allows Denial of Service (DoS)
Product:	[Other] Security Response	Reporter:	Marian Rehak <mrehak>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	akarol, amackenz, amasferr, bbuckingham, bcourt, bkearney, btotty, chazlett, dmetzger, drieden, ehelms, gmccullo, gtanzill, hvyas, jaruga, jhardy, jsherril, lzap, mhulan, mkudlej, mmccune, myarboro, nmoumoul, obarenbo, orabin, pcreech, rchan, rjerrido, roliveri, ruby-packagers-sig, simaishi, smallamp, sokeeffe, tjochec, vondruch
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	puma 4.3.8, puma 5.3.1	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in rubygem-puma. The fix for CVE-2019-16770 was incomplete. The original fix only protected existing connections that had already been accepted from having their requests starved by greedy persistent-connections saturating all threads in the same process. However, new connections may still be starved by greedy persistent-connections saturating all threads in all processes in the cluster. A `puma` server which received more concurrent `keep-alive` connections than the server had threads in its threadpool would service only a subset of connections, denying service to the unserved connections.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-11-13 15:48:35 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:	1964875, 1964966, 1965333
Bug Blocks:	1964876, 1997390

Description Marian Rehak 2021-05-26 09:07:20 UTC

The fix for CVE-2019-16770 was incomplete. The original fix only protected existing connections that had already been accepted from having their requests starved by greedy persistent-connections saturating all threads in the same process. However, new connections may still be starved by greedy persistent-connections saturating all threads in all processes in the cluster. A `puma` server which received more concurrent `keep-alive` connections than the server had threads in its threadpool would service only a subset of connections, denying service to the unserved connections.

External Reference:

https://github.com/puma/puma/security/advisories/GHSA-q28m-8xjw-8vr5

Comment 1 Marian Rehak 2021-05-26 09:07:56 UTC

Created rubygem-puma tracking bugs for this issue:

Affects: fedora-all [bug 1964875]

Comment 2 Mauro Matteo Cascella 2021-05-26 09:56:50 UTC

Upstream issue:
https://github.com/puma/puma/issues/2625

Upstream commit:
https://github.com/puma/puma/commit/df72887170c7ef3614c941c9bdefb4a1f3546ebf

Comment 9 errata-xmlrpc 2021-11-16 14:08:12 UTC

This issue has been addressed in the following products:

  Red Hat Satellite 6.10 for RHEL 7

Via RHSA-2021:4702 https://access.redhat.com/errata/RHSA-2021:4702