CVE-2021-41186
MEDIUM5.9EPSS 0.49%ReDoS vulnerability in parser_apache2
Description
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).
Affected packages (2)
- Bitnami/fluentd>= 0.14.14, < 1.14.2
- RubyGems/fluentd>= 0.14.14, < 1.14.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H |
References (7)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2021-41186
- PATCHhttps://github.com/fluent/fluentd
- WEBhttps://github.com/fluent/fluentd/blob/master/CHANGELOG.md#v1142
- WEBhttps://github.com/fluent/fluentd/commit/5482a3d049dab351de0be68f4b4bc562319d8511
- WEBhttps://github.com/fluent/fluentd/security/advisories/GHSA-hwhf-64mh-r662
- WEBhttps://github.com/github/securitylab-vulnerabilities/blob/52dc4a2a828c6dc24231967c2937ad92038184a9/vendor_reports/GHSL-2021-102-fluent-fluentd.md
- WEBhttps://github.com/rubysec/ruby-advisory-db/blob/master/gems/fluentd/CVE-2021-41186.yml