Key points
- CVE-2026-108268 carries a CVSS 9.1 Critical rating due to TLS session binding failures.
- The flaw affects Privasys Enclave OS Virtual versions before tdx-v0.2.43 and tdx-gpu-v0.6.27.
- An attacker with an enclave TLS private key can relay genuine quotes to unauthorized connections.
Privasys released patches for Enclave OS Virtual to address a critical TLS relay vulnerability identified as CVE-2026-108268. The flaw allows attackers to bypass confidential virtual machine attestation checks by manipulating certificate data. Security teams using older versions must update immediately to prevent unauthorized access to container workloads.
In plain English
The vulnerability exists because the system failed to bind specific data to the active TLS session. The TDX/GPU RA-TLS certificate issuer placed the public-key hash and client nonce in the quote ReportData. However, it omitted a value that should have tied this data to the specific connection. This gap allows an attacker to take a genuine quote from one session and reuse it on another.
The background
Enclave OS Virtual runs container workloads inside confidential virtual machines with end-to-end attestation. According to the NVD record, the issue stems from CWE-346 weaknesses in how certificate data is handled. If an attacker obtains an enclave TLS private key, they can exploit this missing binding. They can then cause a relying party to accept an attacker-terminated connection as if it were the attested enclave.
What changes now
Privasys has released fixes for this issue in specific software versions. The vulnerability is resolved in Enclave OS Virtual version tdx-v0.2.43 and tdx-gpu-v0.6.27. Organizations running versions prior to these releases remain exposed to relay attacks. Users should verify their current version and apply the updates to restore proper attestation integrity.
What to do and how to stay safe: Privasys
- Audit your infrastructure to identify any instances of Privasys Enclave OS Virtual running versions older than tdx-v0.2.43 or tdx-gpu-v0.6.27.
- Apply the vendor-provided updates immediately to patch the TLS certificate binding flaw and restore secure attestation capabilities.
- Monitor network logs for unusual TLS connection patterns or quote reuse attempts that might indicate an active relay attack.
- Review access controls for enclave TLS private keys to ensure they are strictly limited and monitored for unauthorized extraction.
Step-by-step guide: 7 Configuration Errors That Expose Systems to Zero-Day Exploits
General security guidance from the Vuln Post newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is the CVSS score for CVE-2026-108268?
The vulnerability has a CVSS score of 9.1, which is classified as Critical.
Which specific software versions are affected by this flaw?
Privasys Enclave OS Virtual versions prior to tdx-v0.2.43 and tdx-gpu-v0.6.27 are affected.
How does an attacker exploit this vulnerability?
An attacker who obtains an enclave TLS private key can relay a genuine quote onto another connection, causing the relying party to accept the attacker's connection as the attested enclave.
