Introduction
Privilege boundaries in cloud and enterprise environments are only as strong as the hardware memory isolation underneath them. A newly disclosed vulnerability in Intel Xeon 6 processors with Trust Domain Extensions (TDX) could let a privileged local attacker bypass TDX protections and escalate privileges.
Intel's Xeon CPUs run data centers and confidential computing deployments worldwide. TDX is Intel's hardware-based confidential computing feature, designed to isolate virtual machine workloads from the hypervisor and other system software. A security flaw in TDX therefore hits the trust model of cloud and enterprise infrastructure directly.
Technical Information
CVE-2025-22889 is classified as CWE-1260: Improper Handling of Overlap Between Protected Memory Ranges. It affects Intel Xeon 6 processors that support TDX, and it comes down to how the processor and TDX firmware manage memory region boundaries for protected domains.
TDX uses Trust Domain Memory Regions (TDMRs) to isolate guest VM memory from the host and from other VMs. TDMRs are carved from Convertible Memory Regions (CMRs), which the hypervisor manages. The vulnerability arises when the logic that validates region boundaries fails to detect or prevent overlaps between regions assigned to different privilege levels or security domains. If an attacker with local privileged access (such as a compromised hypervisor or VMM) can manipulate memory region definitions to create overlaps, they may gain unauthorized access to protected TDX memory.
That undermines the isolation TDX is supposed to guarantee, because a privileged user may be able to read or modify data inside a guest's protected memory. Earlier joint security reviews by Intel and Microsoft have documented similar weaknesses in TDX's memory range validation, including missing sanity checks and integer overflows. CVE-2025-22889 is about overlapping protected memory ranges, though, not arithmetic errors.
As of this writing, no vulnerable code snippets or public exploitation details are available.
Affected Systems and Versions
- Intel Xeon 6 processors with Intel Trust Domain Extensions (TDX) support
- Only systems where TDX is enabled and used for workload isolation are affected
- Public advisories do not specify any additional version ranges or microcode versions as of this writing
Vendor Security History
Intel's confidential computing technologies, including SGX and TDX, have had several high-impact vulnerabilities in recent years, among them:
- INTEL-SA-01268: Memory management flaws in Xeon 6 processors with TDX or SGX
- INTEL-SA-01278: Memory controller configuration vulnerabilities in Xeon 6
- Multiple issues documented in the Intel-Microsoft TDX joint security review
Intel typically responds with coordinated advisories and microcode updates, but TDX's complexity has made timely patching and validation harder. The steady run of memory management bugs suggests these features still carry architectural and implementation risk.
