{"id":"BIT-fluentd-2021-41186","summary":"ReDoS vulnerability in parser_apache2","details":"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).","aliases":["CVE-2021-41186","GHSA-hwhf-64mh-r662"],"modified":"2026-09-08T08:47:10.538862330Z","published":"2024-03-06T10:52:03.183Z","database_specific":{"severity":"High","cpes":["cpe:2.3:a:fluentd:fluentd:*:*:*:*:*:*:*:*"]},"references":[{"type":"ADVISORY","url":"https://github.com/fluent/fluentd/blob/master/CHANGELOG.md#v1142"},{"type":"ADVISORY","url":"https://github.com/fluent/fluentd/security/advisories/GHSA-hwhf-64mh-r662"},{"type":"WEB","url":"https://github.com/github/securitylab-vulnerabilities/blob/52dc4a2a828c6dc24231967c2937ad92038184a9/vendor_reports/GHSL-2021-102-fluent-fluentd.md"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-41186"}],"affected":[{"package":{"name":"fluentd","ecosystem":"Bitnami","purl":"pkg:bitnami/fluentd"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0.14.14"},{"fixed":"1.14.2"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/fluentd/BIT-fluentd-2021-41186.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}],"schema_version":"1.9.0"}