Key points
- CVE-2026-108268 is rated Critical with a CVSS score of 9.1 by the NVD.
- The vulnerability affects Privasys Enclave OS Virtual versions prior to tdx-v0.2.43 and tdx-gpu-v0.6.27.
- Attackers can relay genuine quotes to trick relying parties into accepting attacker-terminated connections.
Business leaders must ensure their infrastructure runs the latest Privasys Enclave OS versions immediately. A critical vulnerability in the software allows attackers to bypass security checks designed to verify the identity of confidential virtual machines. This flaw undermines the trust model for container workloads that rely on end-to-end attestation.
The National Vulnerability Database assigned CVE-2026-108268 a CVSS score of 9.1, classifying it as Critical. The issue stems from how the TDX/GPU RA-TLS certificate issuer handles session data. It placed the certificate public-key hash and client nonce in the quote ReportData but failed to include a value bound to the active TLS session.
What we know
This weakness, categorized under CWE-346, creates a significant risk for organizations using Privasys Enclave OS Virtual. The software is designed to run container workloads inside confidential virtual machines with strict attestation protocols. However, the missing session-bound value in older builds leaves the attestation process vulnerable to manipulation by sophisticated adversaries.
An attacker who obtains an enclave TLS private key can exploit this gap. They can relay a genuine quote onto a different connection, causing the relying party to accept an attacker-terminated connection as the legitimate, attested enclave. This effectively bypasses the security checks intended to prevent unauthorized access to sensitive data.
The vulnerability affects all versions of Privasys Enclave OS Virtual prior to tdx-v0.2.43. It also impacts GPU-enabled environments running versions prior to tdx-gpu-v0.6.27. According to the NVD record, these specific versions contain the fix for the TLS quote relay bug. Organizations must verify their current version numbers against these thresholds.
Defender's checklist
- Audit all servers running Privasys Enclave OS Virtual to identify versions below tdx-v0.2.43.
- Check GPU-enabled environments for versions older than tdx-gpu-v0.6.27.
- Review logs for any anomalies in TLS session establishment or attestation failures.
- Verify that relying parties are correctly validating the full quote ReportData structure.
What to do and how to stay safe: Privasys
- Inventory all systems using Privasys Enclave OS to determine exposure to CVE-2026-108268.
- Apply the vendor-provided updates to tdx-v0.2.43 or tdx-gpu-v0.6.27 as soon as possible.
- Monitor network traffic for signs of relay attacks or unexpected TLS session terminations.
- Review attestation policies to ensure they require session-bound values in future configurations.
Step-by-step guide: Security Advisories: Small Business Patching Strategy
General security guidance from the Malware Chronicle newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is CVE-2026-108268?
It is a Critical vulnerability in Privasys Enclave OS that allows attackers to bypass attestation by relaying TLS quotes.
Which versions are affected?
Privasys Enclave OS Virtual versions prior to tdx-v0.2.43 and tdx-gpu-v0.6.27 are affected.
Is there a fix available?
Yes, the issue is fixed in versions tdx-v0.2.43 and tdx-gpu-v0.6.27.
