Security readout for executives and security teams
Plain-English summary
CVE-2021-28190 is a buffer overflow in ASUS BMC firmware’s web management certificate-generation function. A remote attacker with privileged access could cause the BMC web service to terminate abnormally, affecting management-plane availability rather than data confidentiality or integrity.
Executive priority
Prioritize this as a management-plane availability and hygiene issue. It is not presented as actively exploited and requires high privileges, but BMC outages can impede server operations, incident response, and remote recovery.
Technical view
The flaw is CWE-120: unchecked input length in the Generate new certificate function on ASUS BMC web management pages. The CVSS 3.1 score is 4.9, with network attack vector, low complexity, high privileges required, no user interaction, and high availability impact only.
Likely exposure
Exposure is limited to listed ASUS BMC firmware versions, including ASMB9-iKVM and multiple ASUS server/workstation BMC products. Risk is highest where BMC web management is reachable beyond a tightly controlled management network and privileged accounts are broadly available.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation evidence. Public details indicate a privileged remote attacker can trigger abnormal web service termination through the vulnerable certificate-generation function, but no exploit status or broader impact is established.
Researcher notes
Affected versions are specifically enumerated in the source bundle, but CPEs are absent. The provided sources do not name a patch level, workaround, or exploit proof. Validation should focus on firmware version matching, BMC exposure, privilege scope, and service stability telemetry.
Mitigation direction
- Check ASUS and TWCERT advisories for fixed firmware or device-specific remediation guidance.
- Update affected BMC firmware when vendor-provided firmware is available.
- Restrict BMC web management access to isolated management networks or VPN.
- Review privileged BMC accounts and remove unnecessary access.
- Monitor BMC web service restarts or unexplained management-plane availability loss.
Validation and detection
- Inventory ASUS BMC firmware models and versions against the affected list.
- Confirm whether BMC web management is reachable from untrusted networks.
- Verify privileged BMC access is limited to required administrators only.
- Review logs for abnormal web service termination around certificate-management activity.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-120: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-28190 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 4.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H1.23.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.9MediumVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://www.asus.com/content/ASUS-Product-Security-Advisory/CVE reference · x_refsource_MISC
- https://www.asus.com/tw/support/callus/CVE reference · x_refsource_MISC
- https://www.twcert.org.tw/tw/cp-132-4560-2f01f-1.htmlCVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.