CVE-2026-16141

Description

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 Vector

References

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