CVE-2026-16141

OpenBMC's IPMI implementation, phosphor-net-ipmid, contains a logic flaw in which an unauthenticated client can force the RAKP Message 1 handler to return before it overwrites the authentication object's constructor defaults. The IPMI service then accepts a RAKP Message 3 whose HMAC is computed with the constant 20-byte 'userKey' initialized from the string '0penBmc' and an often-predictable 'bmcRandomNum'. Several downstream vendors implement phosphor-net-ipmid as their IPMI stack, such as NVIDIA and H3C.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.runzero.com/advisories/openbmc-ipmi-auth-bypass-rakp-cve-2026-16141/
https://www.runzero.com/blog/lights-out-exposed/

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 14:16

Updated : 2026-09-15 15:17

NVD link : CVE-2026-16141

Mitre link : CVE-2026-16141

CVE.ORG link : CVE-2026-16141

JSON object : View

Products Affected

No product.

CWE

CWE-457

Use of Uninitialized Variable

CWE-798

Use of Hard-coded Credentials

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