OpenBMC IPMI Authentication Bypass via Default userKey and Stale Challenge Value

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-16141
StatePUBLISHED
AssignerrunZero
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-09-15 14:16:50 UTC
Updated2026-09-18 19:30:42 UTC
DescriptionOpenBMC'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.

Risk And Classification

Primary CVSS: v3.1 8.1 HIGH from 44488dab-36db-4358-99f9-bc116477f914

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS: 0.003910000 probability, percentile 0.329410000 (date 2026-09-21)

Problem Types: CWE-457 | CWE-798 | CWE-798 CWE-798 Use of Hard-coded Credentials | CWE-457 CWE-457 Use of Uninitialized Variable

VersionSourceTypeScoreSeverityVector
3.144488dab-36db-4358-99f9-bc116477f914Secondary8.1HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
3.1CNACVSS8.1HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA OpenBMC Phosphor-net-ipmid affected ba6efc502e6b1fabb8ed1ca677ae5eedd64b6361 git Not specified

References

ReferenceSourceLinkTags
www.runzero.com/blog/lights-out-exposed 44488dab-36db-4358-99f9-bc116477f914 www.runzero.com
www.runzero.com/advisories/openbmc-ipmi-auth-bypass-rakp-cve-2026-16141 44488dab-36db-4358-99f9-bc116477f914 www.runzero.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: HD Moore of runZero (en)

CNA: Gadi Evron of Knostic (en)

CNA: Tod Beardsley of runZero (en)

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report