{"api_version":"1","generated_at":"2026-04-22T17:46:56+00:00","cve":"CVE-2021-43557","urls":{"html":"https://cve.report/CVE-2021-43557","api":"https://cve.report/api/cve/CVE-2021-43557.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2021-43557","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-43557"},"summary":{"title":"CVE-2021-43557","description":"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. 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Upgrade to APISIX 2.10.2, or apply this commit which provides a normalized $request_uri: https://github.com/apache/apisix/commit/9fc38330e82ce46e2aaabceef7d61708c91782db\n2. Carefully review custom code, find & fix the usage of $request_uri without verification."}]},"nvd":{"publishedDate":"2021-11-22 09:15:00","lastModifiedDate":"2021-11-26 15:47:00","problem_types":["CWE-77"],"metrics":{"baseMetricV3":{"cvssV3":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"NONE","availabilityImpact":"NONE","baseScore":7.5,"baseSeverity":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6},"baseMetricV2":{"cvssV2":{"version":"2.0","vectorString":"AV:N/AC:L/Au:N/C:P/I:N/A:N","accessVector":"NETWORK","accessComplexity":"LOW","authentication":"NONE","confidentialityImpact":"PARTIAL","integrityImpact":"NONE","availabilityImpact":"NONE","baseScore":5},"severity":"MEDIUM","exploitabilityScore":10,"impactScore":2.9,"acInsufInfo":false,"obtainAllPrivilege":false,"obtainUserPrivilege":false,"obtainOtherPrivilege":false,"userInteractionRequired":false}},"configurations":{"CVE_data_version":"4.0","nodes":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:apache:apisix:*:*:*:*:*:*:*:*","versionEndExcluding":"2.10.2","cpe_name":[]}]}]}},"legacy_mitre":{"record":{"CveYear":"2021","CveId":"43557","Ordinal":"220625","Title":"CVE-2021-43557","CVE":"CVE-2021-43557","Year":"2021"},"notes":[{"CveYear":"2021","CveId":"43557","Ordinal":"1","NoteData":"** RESERVED ** This candidate has been reserved by an organization or individual that will use it when announcing a new security problem. When the candidate has been publicized, the details for this candidate will be provided.","Type":"Description","Title":null}]}}}