Bug 2019184 (CVE-2021-41186)

Summary:	CVE-2021-41186 fluentd: ReDoS vulnerability in parser_apache2
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	adsoni, alitman, aos-bugs, bmontgom, dbecker, eparis, ewolinet, jbadiapa, jburrell, jcantril, jjoyce, jokerman, jschluet, lars, lhh, lpeer, mburns, mmagr, mrunge, nstielau, rmccabe, sclewis, slinaber, sponnaga, sradco, tvignaud
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	fluentd 1.14.2	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-11-30 20:09:19 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:	2019185
Bug Blocks:	2019186

Description Guilherme de Almeida Suckevicz 2021-11-01 19:39:50 UTC

Fluentd collects events from various data sources and writes them to files to help unify logging infrastructure. The parser_apache2 plugin in Fluentd v0.14.14 to v1.14.1 suffers from a regular expression denial of service (ReDoS) vulnerability. A broken apache log with a certain pattern of string can spend too much time in a regular expression, resulting in the potential for a DoS attack. This issue is patched in version 1.14.2 There are two workarounds available. Either don't use parser_apache2 for parsing logs (which cannot guarantee generated by Apache), or put patched version of parser_apache2.rb into /etc/fluent/plugin directory (or any other directories specified by the environment variable `FLUENT_PLUGIN` or `--plugin` option of fluentd).

Reference:
https://github.com/fluent/fluentd/security/advisories/GHSA-hwhf-64mh-r662

Comment 1 Guilherme de Almeida Suckevicz 2021-11-01 19:40:05 UTC

Created puppet-fluentd tracking bugs for this issue:

Affects: openstack-rdo [bug 2019185]

Comment 5 Product Security DevOps Team 2021-11-30 20:09:16 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-2021-41186