Critical
Security advisory
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-4300
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 12:53 UTC · Revision 1
Source evidence
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.
osv:CVE-2021-4300
Complete source record
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"url": "https://osv.dev/vulnerability/CVE-2021-4300",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-4300",
"summary": "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.",
"evidence": "osv:CVE-2021-4300",
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"severity": "critical",
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}
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"affected": [
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"type": "GIT",
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"source": "https://github.com/ghostlander/halcyon/commit/0675b25ae9cc10b5fdc8ea3a32c642979762d45e",
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"vanir_signatures_modified": "2026-10-20T14:28:26Z"
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"modified": "2026-10-20T14:28:26.035158872Z",
"provider": "osv",
"references": [
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"https://vuldb.com/?ctiid.217417",
"https://vuldb.com/?id.217417",
"https://github.com/ghostlander/Halcyon/commit/0675b25ae9cc10b5fdc8ea3a32c642979762d45e"
],
"provider_metadata": {}
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"related_cves": [
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"evidence": "/id"
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],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 389062,
"published_at": "2023-01-04T22:15:08.903+00:00"
}