Key points
- CVE-2026-108269 affects Privasys RA-TLS Clients versions prior to 0.5.0 in both Rust and Go.
- The flaw allows an attacker with an enclave private key to relay quotes to different connections.
- The issue is rated CVSS 9.1 Critical and is classified as CWE-346.
Privasys released version 0.5.0 of its RA-TLS Clients library to fix a critical vulnerability that allows attackers to spoof secure enclave connections. The flaw, tracked as CVE-2026-108269, affects all versions of the library prior to 0.5.0. According to the National Vulnerability Database record, the issue carries a CVSS score of 9.1, which is rated as Critical. The vulnerability exists in the multi-language utilities designed for verifying attested TLS connections.
In plain English
The RA-TLS library helps applications verify that they are talking to a trusted, secure computing environment called an enclave. Before version 0.5.0, the verification process in both Rust and Go clients was incomplete. The challenge verifiers checked that the quote ReportData was bound to the certificate public key and the client nonce. However, they did not bind this data to the active TLS session before allowing application traffic to proceed.
This gap means the library accepted a quote that was technically valid but not tied to the specific connection being used. An attacker who had obtained an enclave TLS private key could take a genuine quote from one session and relay it to another. The client would accept this relayed quote as proof of identity, allowing the attacker to impersonate the attested enclave on a different connection.
The background
The vulnerability is classified under CWE-346, which relates to origin validation errors. The National Vulnerability Database describes the issue as a failure to properly bind the attestation quote to the specific network session. This allows for a relay attack where the cryptographic proof of the enclave's identity is detached from the actual communication channel.
Privasys provides these utilities to help developers build secure systems that rely on remote attestation. The flaw was present in the logic that permits application traffic after the initial verification steps. By not linking the quote to the active TLS session, the library created a window where an attacker could substitute a valid quote for an invalid connection.
What changes now
Privasys has released version 0.5.0 of the RA-TLS Clients library, which fixes this issue. The update ensures that the quote ReportData is properly bound to the active TLS session. This prevents attackers from relaying genuine quotes to unauthorized connections. Organizations using versions older than 0.5.0 are advised to upgrade to the patched version immediately to mitigate the risk of remote attestation bypass.
What to do and how to stay safe: Privasys
- Inventory systems using Privasys RA-TLS Clients to identify versions prior to 0.5.0.
- Upgrade Rust and Go applications to version 0.5.0 or later once the vendor provides the update.
- Monitor network logs for unusual TLS session patterns that might indicate relay attempts.
- Review attestation verification logic in custom implementations for similar binding gaps.
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
Which versions of the Privasys RA-TLS library are affected?
All versions of the Privasys RA-TLS Clients library prior to 0.5.0 are affected by this vulnerability.
What is the CVSS score for CVE-2026-108269?
The National Vulnerability Database rates CVE-2026-108269 as CVSS 9.1, which is considered Critical.
Is there a fix available for this vulnerability?
Yes, the issue is fixed in version 0.5.0 of the Privasys RA-TLS Clients library.
