{"id":"CVE-2021-43557","details":"The uri-block plugin in Apache APISIX before 2.10.2 uses $request_uri without verification. The $request_uri is the full original request URI without normalization. This makes it possible to construct a URI to bypass the block list on some occasions. For instance, when the block list contains \"^/internal/\", a URI like `//internal/` can be used to bypass it. Some other plugins also have the same issue. And it may affect the developer's custom plugin.","aliases":["BIT-apisix-2021-43557"],"modified":"2026-07-09T05:45:29.884655Z","published":"2021-11-22T09:15:07.627Z","references":[{"type":"ADVISORY","url":"http://www.openwall.com/lists/oss-security/2021/11/22/1"},{"type":"ADVISORY","url":"http://www.openwall.com/lists/oss-security/2021/11/22/2"},{"type":"EVIDENCE","url":"http://www.openwall.com/lists/oss-security/2021/11/23/1"},{"type":"EVIDENCE","url":"https://lists.apache.org/thread/18jyd458ptocr31rnkjs71w4h366mv7h"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/apache/apisix","events":[{"introduced":"0"},{"fixed":"19587ed9f71dd20c5e8dbdc2f79c8f96296e73e3"}],"database_specific":{"cpe":"cpe:2.3:a:apache:apisix:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"fixed":"2.10.2"}],"source":"CPE_RANGE"}}],"versions":["2.10.1","2.10.0","v0.9","0.9-RC1","v0.7","v0.5","v0.4.1","v0.4","v0.3-1","v0.3","v0.2"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-43557.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"}]}