CVE-2026-50031: FreeIPMI Buffer Overflow in ipmi-oem Commands – Patch Guide

Technical summary

The vulnerability resides in the ipmi-oem subcommands for Dell and Fujitsu OEM extensions within FreeIPMI. When these commands send IPMI requests to a platform management controller and parse the response, they fail to properly validate the bounds of response message data before writing it into fixed-size buffers. This classic stack-based buffer overflow (CWE-121) occurs during response parsing, not request formation. An attacker who controls or has compromised the IPMI server—or who can perform a man-in-the-middle attack on the IPMI communication channel—can craft oversized response payloads that overflow these buffers, corrupting memory and leading to denial of service or code execution in the context of the user running ipmi-oem.

Business impact

If your organization uses FreeIPMI to manage Dell or Fujitsu hardware, this vulnerability could allow an attacker with network access to your IPMI infrastructure to deny service to management tools or gain code execution on administrative workstations. The impact escalates if those workstations run with elevated privileges or hold credentials for other systems. IPMI is often deployed on isolated management networks, but lateral movement from compromised servers or supply-chain attacks on IPMI firmware could expose this path. Organizations should treat IPMI networks as security perimeters and ensure management clients are patched.

Affected systems

FreeIPMI versions prior to 1.6.18 are vulnerable. The risk is highest if you actively use the `ipmi-oem` command with Dell or Fujitsu subcommands. Exposure depends on your environment: organizations with dedicated IPMI VLANs and strict access controls face lower risk than those with IPMI accessible from broader networks. Any tool or script that calls FreeIPMI's ipmi-oem commands internally should also be reviewed for potential exploitation if the IPMI server can be compromised.

Exploitability

Exploitation requires network access to an IPMI server that will return a response to the vulnerable subcommand. The attacker does not need credentials if IPMI authentication is not enforced (a common misconfiguration), though authenticated channels can also be attacked if the attacker has compromised the server or can intercept unencrypted IPMI traffic. The complexity is low: sending a malformed response is trivial once an attacker has positioned themselves on the network path. The CVSS score of 7.5 reflects high availability impact (denial of service) without confidentiality or integrity compromise in the default scoring; however, code execution may be feasible with payload crafting. This is not yet tracked in CISA's KEV catalog, suggesting limited in-the-wild exploitation to date, but the barrier to weaponization is low.

Remediation

Upgrade FreeIPMI to version 1.6.18 or later. Before patching, segment IPMI management networks from general-purpose networks, enforce strong authentication on IPMI interfaces, and monitor for unusual IPMI traffic. If you cannot patch immediately, disable the use of `ipmi-oem dell` and `ipmi-oem fujitsu` commands, or restrict them to trusted administrative interfaces only. Review any automation or monitoring scripts that invoke these commands and verify they connect only to known, trusted IPMI endpoints.

Patch guidance

1. Verify your current FreeIPMI version: run `ipmi-sensors --version` or check your package manager. 2. Update to FreeIPMI 1.6.18 or later using your distribution's package manager or by compiling from the FreeIPMI project repository. 3. Test the updated version in a non-production environment first, especially if you have custom scripts or integrations. 4. After patching, restart or reconnect any active management sessions to ensure new code is in use. 5. If you maintain a custom or embedded build of FreeIPMI, cherry-pick the relevant buffer overflow fixes from the upstream project or apply vendor patches if available through your hardware OEM.

Detection guidance

Monitor for unusual IPMI command traffic, particularly repeated or failed `ipmi-oem` requests. Log all invocations of ipmi-oem commands and their return codes; a crash or segmentation fault may indicate an exploitation attempt. On systems running vulnerable versions, enable core dumps and collect crash logs for forensic analysis. Network-level detection is difficult without IPMI protocol inspection; however, if IPMI is on a dedicated VLAN, monitor for unexpected external connections to IPMI ports. Check process logs on management workstations for unexpected child processes or crashes following ipmi-oem command execution.

Why prioritize this

Although this is a HIGH-severity vulnerability with a 7.5 CVSS score, patch urgently only if your organization actively uses the affected Dell or Fujitsu OEM subcommands on systems that connect to potentially untrusted or internet-accessible IPMI servers. Most enterprises restrict IPMI to management networks with strict firewall rules, significantly reducing attack surface. However, if your IPMI infrastructure is less isolated or if you operate in a high-threat environment, prioritize this update. The lack of KEV activity suggests this is not yet a widespread exploitation target, but that provides no guarantee—treat it as a medium-to-high priority based on your specific IPMI architecture and risk posture.

Risk score, explained

The CVSS 3.1 score of 7.5 reflects attack vector 'network' (attacker needs only network access), low attack complexity, no privilege requirement, no user interaction, and high availability impact. Confidentiality and integrity are not affected under the base scoring. However, the real-world risk is moderated by the assumption that IPMI is typically deployed on isolated networks. The vulnerability does not appear on CISA's KEV list, indicating limited known exploitation in the wild, but the technical barrier to creating a working exploit is low. Organizations should not dismiss this as low-risk simply because the score is below 8.0; context matters.

Frequently asked questions