Privasys Go Quote Relay Bug Bypasses Attestation Checks in Pre-v0.5.1 Versions

A critical remote attestation flaw in Privasys Go allows attackers to relay enclave quotes and impersonate trusted connections. The National Vulnerability Database assigned CVE-2026-108267 a CVSS score of 9.1, classifying the issue as critical. The vulnerability stems from how challenge-mode RA-TLS certificates bind quote ReportData to the certificate public key and client nonce, but fail to bind them to the active TLS session. This gap enables an attacker who has obtained an enclave TLS private key to replay a genuine quote onto a different connection.

A relying party may then accept the handshake as a valid attested enclave connection, even though it was terminated by the attacker. The issue impacts all versions of Privasys Go prior to privasys-v0.5.1-go1.26.5. Privasys Go is a maintained fork of the Go programming language that adds RA-TLS support to the crypto/tls package. The weakness is categorized under CWE-346, which relates to origin validation errors. The flaw was fixed in the privasys-v0.5.1-go1.26.5 release, according to the NVD record.

How it unfolded

• Privasys Go added RA-TLS support to the Go crypto/tls package to enable remote attestation.
• Developers implemented challenge-mode certificates that bound quote ReportData to public keys and nonces.
• The implementation failed to bind the data to the active TLS session, creating a relay vulnerability.

Who is affected

Organizations using Privasys Go versions older than privasys-v0.5.1-go1.26.5 are affected by this vulnerability. Any system relying on RA-TLS for enclave attestation is at risk of accepting forged handshake terminations. If an attacker obtains an enclave TLS private key, they can exploit the missing session binding to relay a genuine quote. This allows the attacker to masquerade as a trusted enclave to relying parties. The impact is severe because the relying party believes it is communicating with an attested enclave when it is not.

The fix

The vendor released a fix in version privasys-v0.5.1-go1.26.5. Users of Privasys Go should upgrade to this version or later to mitigate the risk. The update corrects the binding of quote ReportData to include the active TLS session, preventing relay attacks. No other patches or workarounds are mentioned in the source material. Organizations must verify their current version and apply the update promptly to restore proper attestation integrity.

What to do and how to stay safe: Privasys Go

• Audit all systems running Privasys Go to identify versions prior to privasys-v0.5.1-go1.26.5.
• Upgrade affected installations to the patched version as soon as possible to close the relay gap.
• Monitor network logs for unusual TLS handshake patterns that may indicate relay attempts.
• Review access controls for enclave TLS private keys to prevent unauthorized extraction.

Step-by-step guide: What Is Virtual Patching: How It Works Without Code Changes

General security guidance from the RedTeam Tribune newsroom. It is not confirmed advice from the organisations named in this story.

Frequently asked questions

What is CVE-2026-108267?

It is a critical vulnerability in Privasys Go that allows attackers to relay RA-TLS attestation certificates.

Which versions are affected?

All versions of Privasys Go prior to privasys-v0.5.1-go1.26.5 are vulnerable to this flaw.

Is there a fix available?

Yes, the issue is fixed in version privasys-v0.5.1-go1.26.5, according to the NVD record.