CVE-2026-33923: Update bundle signature bypass in Guardian/CMC before 26.4.0
A signature verification vulnerability was discovered in the update installation functionality due to inconsistent validation of the update bundle contents. An attacker with administrative privileges can remotely supply a crafted update bundle that passes signature verification but runs an unsigned script when the bundle is installed. The script runs with root privileges, allowing the attacker to read or modify sensitive data, change the appliance configuration, or shut down the appliance.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 26.4.0
Event History
Frequently Asked Questions
Who can exploit this vulnerability?
An attacker needs administrative privileges on Guardian/CMC and network access sufficient to remotely provide a crafted update bundle. It is therefore primarily a risk where administrative accounts or their credentials are compromised or misused.
What is the impact of a successful exploit?
The crafted bundle can cause an unsigned script to run as root during installation. This can let the attacker read or modify sensitive data, alter appliance configuration, or shut down the appliance.
Which versions need remediation?
Guardian/CMC versions before 26.4.0 are affected according to the available information.