CVE-2026-5818 - Vulnerability Details - OpenCVE

Incorrect check of function return value in Caliptra Core Runtime Firmware (ActivateFirmwareCmd::activate_fw modules) allows bypass of Caliptra Core's verification of the MCU FW during a hitless update. This issue affects Core Runtime Firmware: from 2.0.0 through 2.0.1, 2.1.0.

Attack Vector Adjacent Network

Attack Complexity Low

Privileges Required High

Attack Requirements Present

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact High

Subsequent System Integrity Impact High

Subsequent System Availability Impact High

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable no

Technical Impact partial

Vendors	Products
Caliptra	Core Runtime Firmware

No data.

No data.

References

Link	Providers
https://github.com/chipsalliance/caliptra-sw/security/advisories/GHSA-456r-gcjr-6rxq

History

Wed, 24 Jun 2026 16:45:00 +0000

Type	Values Removed	Values Added
First Time appeared		Caliptra Caliptra core Runtime Firmware
Vendors & Products		Caliptra Caliptra core Runtime Firmware

Wed, 24 Jun 2026 13:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Wed, 24 Jun 2026 00:15:00 +0000

Type	Values Removed	Values Added
Description		Incorrect check of function return value in Caliptra Core Runtime Firmware (ActivateFirmwareCmd::activate_fw modules) allows bypass of Caliptra Core's verification of the MCU FW during a hitless update. This issue affects Core Runtime Firmware: from 2.0.0 through 2.0.1, 2.1.0.
Title		MCU Firmware Update Authentication Bypass on Caliptra Core
Weaknesses		CWE-253
References		https://github.com/chipsalliance/caliptra-sw/security/advisories/GHSA-456r-gcjr-6rxq
Metrics		cvssV4_0 `{'score': 7.2, 'vector': 'CVSS:4.0/AV:A/AC:L/AT:P/PR:H/UI:N/VC:N/VI:H/VA:H/SC:H/SI:H/SA:H'}`

MITRE

Status: PUBLISHED

Assigner: Caliptra

Published: 2026-06-23T23:50:06.556Z

Updated: 2026-06-24T13:04:40.166Z

Reserved: 2026-04-08T15:45:10.928Z

Link: CVE-2026-5818

Vulnrichment

Updated: 2026-06-24T13:04:36.471Z

NVD

No data.

Redhat

No data.

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