Key points
- CVE-2026-108265 is rated CVSS 9.1 Critical by the NVD.
- The flaw affects Privasys Enclave OS Mini versions before wasm-v0.40.0.
- The vulnerability stems from missing TLS session binding in quote ReportData.
Privasys Enclave OS Mini contains a critical vulnerability that allows attackers to perform relay attacks on Intel SGX attestation processes. The issue, tracked as CVE-2026-108265, affects all versions of the runtime prior to wasm-v0.40.0. The National Vulnerability Database rates the flaw as Critical with a CVSS score of 9.1.
The vulnerability exists because the Remote Attestation over TLS (RA-TLS) challenge certificate path fails to bind a value to the active TLS session. Specifically, the implementation places the certificate public-key hash and client nonce into the quote ReportData but omits session-specific binding. This design gap allows an attacker who has obtained an enclave TLS private key to relay a genuine quote onto a different connection.
Technical Mechanics of the Flaw
According to the NVD record, the weakness is classified under CWE-346, which relates to insufficient verification of data authenticity. Enclave OS Mini is a Rust-based runtime designed for confidential applications inside Intel SGX enclaves. The RA-TLS protocol is meant to ensure that the party holding the private key is the same entity that generated the SGX quote. By omitting the TLS session binding, the protocol loses this link.
An attacker can exploit this by intercepting a legitimate attestation request. If the attacker possesses the enclave TLS private key, they can take a valid quote generated for one session and present it as valid for another. This causes the relying party to accept an attacker-terminated connection as the attested enclave, effectively breaking the trust chain.
Affected Components and Versions
The issue specifically impacts Privasys Enclave OS Mini. Any deployment using a version older than wasm-v0.40.0 is vulnerable to this relay attack. The fix was introduced in version wasm-v0.40.0, which adds the necessary binding to prevent quote reuse across different TLS sessions. System administrators should audit their environments to identify any instances of the affected runtime.
Next steps
Organizations using Privasys Enclave OS Mini must verify their current version immediately. Upgrading to wasm-v0.40.0 or later resolves the issue by ensuring that quotes are cryptographically bound to the specific TLS session in which they were generated. This prevents the reuse of quotes on unrelated connections.
What to do and how to stay safe: Privasys
- Audit your infrastructure to identify all instances of Privasys Enclave OS Mini running versions prior to wasm-v0.40.0.
- Plan an immediate upgrade to version wasm-v0.40.0 or later to apply the vendor-provided fix for the missing TLS binding.
- Review logs for any anomalous attestation requests or unexpected connection terminations that could indicate a relay attempt.
- Ensure that relying parties validate the freshness and session context of SGX quotes during the attestation process.
Step-by-step guide: Emergency Patching Checklist for Critical System Fixes
General security guidance from the SecOps Monitor newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is the CVSS score for CVE-2026-108265?
The National Vulnerability Database rates CVE-2026-108265 as Critical with a CVSS score of 9.1.
Which versions of Enclave OS Mini are affected?
All versions of Privasys Enclave OS Mini prior to wasm-v0.40.0 are affected by this vulnerability.
How does the attacker exploit this flaw?
An attacker with the enclave TLS private key can relay a genuine quote to another connection, causing the relying party to accept an attacker-terminated connection as the attested enclave.
