{"id":"CVE-2021-4300","aliases":["EUVD-2021-34135","GHSA-hxx9-636q-j4p5"],"status":"published","title":"ghostlander Halcyon Block Verification main.cpp AddToBlockIndex access control","description":"A vulnerability has been found in ghostlander Halcyon and classified as critical. Affected by this vulnerability is the function CBlock::AddToBlockIndex of the file src/main.cpp of the component Block Verification. The manipulation leads to improper access controls. The attack can be launched remotely. Upgrading to version 1.1.1.0-hal is able to address this issue. The identifier of the patch is 0675b25ae9cc10b5fdc8ea3a32c642979762d45e. It is recommended to upgrade the affected component. The identifier VDB-217417 was assigned to this vulnerability.","severity":{"version":"3.1","score":6.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00715,"percentile":0.54208,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-284"],"published":"2023-01-04T21:14:42Z","modified":"2026-10-20T14:28:26Z","products":[{"vendor":"ghostlander","product":"halcyon"},{"vendor":"halcyon_project","product":"halcyon"}],"references":[{"url":"https://vuldb.com/?id.217417","tags":["vdb-entry","technical-description","x_transferred","Permissions Required","Third Party Advisory","report"]},{"url":"https://vuldb.com/?ctiid.217417","tags":["signature","permissions-required","x_transferred","Permissions Required","Third Party Advisory","report"]},{"url":"https://github.com/ghostlander/Halcyon/commit/0675b25ae9cc10b5fdc8ea3a32c642979762d45e","tags":["patch","x_transferred","Patch","fix"]},{"url":"https://github.com/ghostlander/Halcyon/releases/tag/v1.1.1.0-hal","tags":["patch","x_transferred","Release Notes","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-4300"},{"url":"https://github.com/advisories/GHSA-hxx9-636q-j4p5"}],"sources":{"cve":[{"id":"CVE-2021-4300","title":"ghostlander Halcyon Block Verification main.cpp AddToBlockIndex access control","description":"A vulnerability has been found in ghostlander Halcyon and classified as critical. Affected by this vulnerability is the function CBlock::AddToBlockIndex of the file src/main.cpp of the component Block Verification. The manipulation leads to improper access controls. The attack can be launched remotely. Upgrading to version 1.1.1.0-hal is able to address this issue. The identifier of the patch is 0675b25ae9cc10b5fdc8ea3a32c642979762d45e. It is recommended to upgrade the affected component. The identifier VDB-217417 was assigned to this vulnerability.","status":"published","published":"2023-01-04T21:14:42.593Z","modified":"2024-08-03T17:23:10.41Z","cvss":[{"version":"3.1","score":6.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"cna"},{"version":"3.0","score":6.3,"vector":"CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"cna"},{"version":"2.0","score":6.5,"vector":"AV:N/AC:L/Au:S/C:P/I:P/A:P","assessor":"cna"}],"cwes":["CWE-284"],"updated_at":"2026-11-02T14:33:08.045407Z"}],"euvd":[{"id":"EUVD-2021-34135","description":"A vulnerability has been found in ghostlander Halcyon and classified as critical. Affected by this vulnerability is the function CBlock::AddToBlockIndex of the file src/main.cpp of the component Block Verification. The manipulation leads to improper access controls. The attack can be launched remotely. Upgrading to version 1.1.1.0-hal is able to address this issue. The identifier of the patch is 0675b25ae9cc10b5fdc8ea3a32c642979762d45e. It is recommended to upgrade the affected component. The identifier VDB-217417 was assigned to this vulnerability.","status":"published","published":"2023-01-04T21:14:42Z","modified":"2024-08-03T17:23:10Z","cvss":[{"version":"3.1","score":6.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium"}],"updated_at":"2026-11-03T03:25:10.418596Z"}],"ghsa":[{"id":"GHSA-hxx9-636q-j4p5","title":"A vulnerability has been found in ghostlander Halcyon and classified as critical. Affected by...","description":"A vulnerability has been found in ghostlander Halcyon and classified as critical. Affected by this vulnerability is the function CBlock::AddToBlockIndex of the file src/main.cpp of the component Block Verification. The manipulation leads to improper access controls. The attack can be launched remotely. Upgrading to version 1.1.1.0-hal is able to address this issue. The name of the patch is 0675b25ae9cc10b5fdc8ea3a32c642979762d45e. It is recommended to upgrade the affected component. The identifier VDB-217417 was assigned to this vulnerability.","status":"published","published":"2023-01-05T00:30:17Z","modified":"2023-02-03T05:01:54Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-284"],"updated_at":"2026-11-02T14:53:03.850376Z"}],"nvd":[{"id":"CVE-2021-4300","description":"A vulnerability has been found in ghostlander Halcyon and classified as critical. Affected by this vulnerability is the function CBlock::AddToBlockIndex of the file src/main.cpp of the component Block Verification. The manipulation leads to improper access controls. The attack can be launched remotely. Upgrading to version 1.1.1.0-hal is able to address this issue. The identifier of the patch is 0675b25ae9cc10b5fdc8ea3a32c642979762d45e. It is recommended to upgrade the affected component. The identifier VDB-217417 was assigned to this vulnerability.","status":"published","published":"2023-01-04T22:15:08.903Z","modified":"2026-06-17T04:19:27.37Z","cvss":[{"version":"3.1","score":6.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L","level":"medium","assessor":"secondary"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":6.5,"vector":"AV:N/AC:L/Au:S/C:P/I:P/A:P","level":"medium","assessor":"secondary"}],"cwes":["CWE-284"],"updated_at":"2026-11-02T14:07:07.323379Z"}],"osv":[{"id":"CVE-2021-4300","description":"A vulnerability has been found in ghostlander Halcyon and classified as critical. Affected by this vulnerability is the function CBlock::AddToBlockIndex of the file src/main.cpp of the component Block Verification. The manipulation leads to improper access controls. The attack can be launched remotely. Upgrading to version 1.1.1.0-hal is able to address this issue. The identifier of the patch is 0675b25ae9cc10b5fdc8ea3a32c642979762d45e. It is recommended to upgrade the affected component. The identifier VDB-217417 was assigned to this vulnerability.","status":"published","published":"2023-01-04T22:15:08.903Z","modified":"2026-10-20T14:28:26.035158872Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-02T15:44:21.557945Z"}]}}