{"schemaVersion":3,"id":"CVE-2021-21369","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"Hyperledger Besu is an open-source, MainNet compatible, Ethereum client written in Java. In Besu before version 1.5.1 there is a denial-of-service vulnerability involving the HTTP JSON-RPC API service. If username and password authentication is enabled for the HTTP JSON-RPC API service, then prior to making any requests to an API endpoint the requestor must use the login endpoint to obtain a JSON web token (JWT) using their credentials. A single user can readily overload the login endpoint with invalid requests (incorrect password). As the supplied password is checked for validity on the main vertx event loop and takes a relatively long time this can cause the processing of other valid requests to fail. A valid username is required for this vulnerability to be exposed. This has been fixed in version 1.5.1.","dates":{"published":"2021-03-09T18:10:18.000Z","modified":"2024-08-03T18:09:15.981Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":6.5,"severity":"medium","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":6.5,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":6.5,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":4,"severity":"medium","vector":"AV:N/AC:L/Au:S/C:N/I:N/A:P","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.01668,"percentile":0.7642,"severity":"low","asOf":"2026-10-19T00:00:00.000Z","change":{"pp":0.16500000000000004,"baselineDate":"2026-09-19T00:00:00.000Z","baselineScore":0.01503},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.01668,"percentile":0.7642}],"last30":[{"date":"2026-09-19T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01503,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.01668,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.01668,"percentile":0.7642}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-400","name":"Uncontrolled Resource Consumption","description":"The product does not properly control the allocation and maintenance of a limited resource.","type":"weakness","status":"Draft","abstraction":"Class","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/400.html"}],"affected":[{"vendor":"hyperledger","product":"besu","name":"besu","label":"besu","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 1.5.1","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 1.5.1","eol":null,"hubHref":"/vendor/hyperledger/besu"},{"vendor":"linuxfoundation","product":"besu","name":"besu","label":"besu","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 1.5.1","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 1.5.1","eol":null,"hubHref":"/vendor/linuxfoundation/besu"}],"affectedCount":2,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://github.com/hyperledger/besu/security/advisories/GHSA-qgfj-mjpc-7w3q","label":"github.com/hyperledger/besu/security/advisories/GHSA-qgfj-mjpc-7w3q","hostname":"github.com","tags":["X Refsource CONFIRM","Third Party Advisory"]},{"url":"https://github.com/hyperledger/besu/blob/master/CHANGELOG.md#151","label":"github.com/hyperledger/besu/blob/master/CHANGELOG.md","hostname":"github.com","tags":["X Refsource MISC","Release Notes","Third Party Advisory"]},{"url":"https://github.com/hyperledger/besu/pull/1144","label":"github.com/hyperledger/besu/pull/1144","hostname":"github.com","tags":["X Refsource MISC","Patch","Third Party Advisory"]},{"url":"https://github.com/hyperledger/besu/commit/06e35a58c07a30c0fbdc0aae45a3e8b06b53c022","label":"github.com/hyperledger/besu/commit/06e35a58c07a30c0fbdc0aae45a3e8b06b53c022","hostname":"github.com","tags":["X Refsource MISC","Patch","Third Party Advisory"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2021-03-09T18:10:18.000Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2024-08-03T18:09:15.981Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":26,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-19T21:02:53.430Z","stale":false,"partial":false}}