Security readout for executives and security teams
Plain-English summary
This issue can let an unauthenticated network attacker crash or disrupt a server’s BMC management interface when it runs OpenBMC 2.9 with IPMI LAN+ exposed. It affects availability, not data theft or data modification based on the provided CVSS vector.
Executive priority
Treat this as a high-priority infrastructure resilience issue for environments with OpenBMC-based servers. The main business risk is loss of out-of-band management during incidents or outages, especially if BMC networks are exposed beyond tightly controlled administration paths.
Technical view
CVE-2021-39295 is a CWE-400 resource-consumption denial-of-service flaw in OpenBMC 2.9 netipmid, the IPMI LAN+ interface. The CVSS 3.1 vector is AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H, indicating remote unauthenticated availability impact.
Likely exposure
Exposure is most likely where BMC management interfaces running OpenBMC 2.9 expose IPMI LAN+ over the network. Internet-facing or broadly reachable management networks are higher risk. The source bundle does not provide complete affected vendor, product, or CPE data.
Exploitation context
The bundle does not show CISA KEV listing or cited evidence of active exploitation. The CVSS vector indicates exploitation is network-accessible, low-complexity, and unauthenticated, but the known impact is denial of service to the BMC interface.
Researcher notes
Evidence is limited to the CVE description, CVSS vector, CWE-400 classification, and listed advisories. The bundle names OpenBMC 2.9 and netipmid/IPMI LAN+ but does not include a specific fixing commit, patched version, or complete vendor affected-product matrix.
Mitigation direction
- Check OpenBMC, hardware vendor, and Intel guidance for fixed firmware or supported mitigations.
- Inventory BMC firmware versions and prioritize systems running OpenBMC 2.9.
- Restrict IPMI LAN+ access to trusted management networks only.
- Remove BMC interfaces from internet or broad enterprise network exposure.
- Monitor BMC availability and management-interface failures until remediation is complete.
Validation and detection
- Identify systems using OpenBMC 2.9 or vendor firmware derived from it.
- Confirm whether netipmid or IPMI LAN+ is enabled on those BMCs.
- Review network paths to BMC management interfaces for untrusted access.
- Check vendor advisories for affected model and firmware mapping.
- Avoid production validation using crafted IPMI messages.
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-400: 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-2021-39295 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
- High
- CVSS
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/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:N/UI:N/S:U/C:N/I:N/A:H3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://openbmc.org/CVE reference
- https://github.com/openbmc/openbmcCVE reference
- https://github.com/openbmc/docs/blob/master/release/release-notes.mdCVE reference
- https://github.com/openbmc/openbmc/issues/3811CVE reference
- https://github.com/google/security-research/security/advisories/GHSA-gg9x-v835-m48qCVE reference
- https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00737.htmlCVE reference
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.
Uncontrolled Resource Consumption
Uncontrolled Resource Consumption represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.