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TI-2021-03158 Aliases CVE-2021-4300GHSA-hxx9-636q-j4p5

ghostlander Halcyon Block Verification main.cpp AddToBlockIndex access control

Priority MEDIUM 43CWE-284Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-284.

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.

Why it matters now

EPSS 0.00715 53rd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
ghostlanderHalcyonall versions—No fix listedCNA
  • Halcyon Vendorghostlander Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:halcyon_project:halcyon:*:*:*:*:*:*:*:*before 1.1.1.0VulnerableHalcyon Project
  • cpe:2.3:a:halcyon_project:halcyon:*:*:*:*:*:*:*:* Versions before 1.1.1.0 Vulnerable ·Halcyon Project

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-4300
  2. 2026-10-03 Alias added: GHSA-hxx9-636q-j4p5
  3. 2026-10-09 EPSS moved to the 50th–90th percentile

References

Patch 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences