EUVD-2026-56509
GHSA-x334-5fcx-5jhr
Severity by source
CVSS:4.0/AV:L/AC:H/AT:N/PR:H/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Local access and high privileges required per attack description; scope change to C reflects SMM escape impacting hypervisor and co-tenant systems beyond OS boundary.
Primary rating from Vendor (intel).
CVSS VectorVendor: intel
Lifecycle Timeline
2DescriptionCVE.org
Improper access control in the firmware for some in Alias Checking Trusted Module for some Intel(R) Xeon(R) processors may allow an escalation of privilege. Startup code and SMM adversary with a privileged user combined with a high complexity attack may enable escalation of privilege. This result may potentially occur via local access when attack requirements are not present without special internal knowledge and requires no user interaction. The potential vulnerability may impact the confidentiality (high), integrity (high) and availability (none) of the vulnerable system, resulting in subsequent system confidentiality (high), integrity (high) and availability (none) impacts.
AnalysisAI
Privilege escalation in the Alias Checking Trusted Module (ACTM) firmware for certain Intel Xeon processors allows a local privileged attacker to escalate to System Management Mode (SMM) execution, achieving high confidentiality and integrity impact across both the directly compromised system and subsequent systems such as co-hosted hypervisors or tenant workloads. The attack requires high-complexity local technique combined with pre-existing privileged user access, placing it firmly in the advanced persistent threat actor category. …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Exploitation requires all of the following concurrent conditions: (1) local access to the target system - the AV:L CVSS metric confirms remote network exploitation is not possible; (2) a high-privilege user account (PR:H), meaning administrator or root-level OS access is a hard prerequisite - unauthenticated or low-privilege attackers cannot directly trigger this flaw; (3) a high-complexity attack (AC:H) involving specific interaction with startup code or SMM execution windows, requiring internal firmware knowledge and precise sequencing rather than a simple one-shot exploit; and (4) the target must be an Intel Xeon processor model incorporating the Alias Checking Trusted Module in its firmware - consumer and mobile Intel processors are not indicated as affected. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 4.0 score of 8.5 reflects a genuine high-severity risk, but real-world exploitation difficulty is substantial: AV:L restricts exploitation to those with existing local or OS-level access, AC:H indicates a non-trivial attack requiring specific conditions or internal firmware knowledge, and PR:H narrows the exploitable population to actors who already hold administrator or root privileges. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | Full exploit scenario with step-by-step reproduction available after sign-in. |
| Remediation | The primary remediation is to apply the firmware update identified in Intel Security Advisory INTEL-SA-01439 at https://intel.com/content/www/us/en/security-center/advisory/intel-sa-01439.html. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours, obtain Intel advisory INTEL-SA-01439 and cross-reference your Xeon processor inventory against the affected processor generations listed; simultaneously audit and restrict local administrative access on affected systems. …
Sign in for detailed remediation steps and compensating controls.
Threat intelligence, references, and detailed analysis are available after sign-in.
Same weakness CWE-284 – Improper Access Control
View allSame technique Privilege Escalation
View allShare
External POC / Exploit Code
Leaving vuln.today