Findings

Vulnerability · CVE-2021-28199

ASUS asmb9-ikvm_firmware Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

Published Jun 22, 2026 · corrected/updated Jun 22, 2026 · ASUS asmb9-ikvm_firmware · evidence confidence very high

The specific function in ASUS BMC’s firmware Web management page (Modify user’s information function) does not verify the string length entered by users, resulting in a Buffer overflow vulnerability. As obtaining the privileged permission, remote attackers use the leakage to abnormally terminate the Web service.

Grounded briefings

Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.

Executive

CVE-2021-28199 is a unknown public vulnerability record for ASUS asmb9-ikvm_firmware. CISA lists it as known exploited. Published remediation guidance: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.

System administrator

Identify whether ASUS asmb9-ikvm_firmware is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: ASUS asmb9-ikvm_firmware. Published remediation guidance: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.

Security analyst

Signals on file: EPSS 1.8%. CISA lists it as known exploited. Sources contributing to this record: epss, vulncheck_kev. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.

Exploitation and remediation

  • Exploitation evidence

    Confirmed in CISA KEV since Jun 22, 2026. Listed in CISA KEV and VulnCheck KEV.

  • Patch and remediation

    Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

  • Safe detection guidance

    Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Jun 22, 2026 · VulnCheck KEV

    Detected

    The specific function in ASUS BMC’s firmware Web management page (Modify user’s information function) does not verify the string length entered by users, resulting in a Buffer overflow vulnerability. As obtaining the privileged permission, remote attackers use the leakage to abnormally terminate the Web service.

  2. Jun 22, 2026 · CISA KEV

    Known exploited

    Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

Affected

  • vendor ASUS asmb9-ikvm_firmwareversion unspecified

Sources

  • FIRST EPSSExploitation probabilityCVE-2021-28199

    30-day exploitation probability 1.8%

    first.org
  • VulnCheck KEVConfirmed exploitationCVE-2021-28199

    The specific function in ASUS BMC’s firmware Web management page (Modify user’s information function) does not verify the string length entered by users, resulting in a Buffer overflow vulnerability. As obtaining the privileged permission, remote attackers use the leakage to abno

    vulncheck.com

References