Enclave OS Virtual: RA-TLS challenge certificates not bound to TLS session
Summary
Enclave OS (Virtual) runs container workloads in confidential virtual machines and uses RA-TLS certificates with attestation quotes to prove the enclave's identity to clients. In affected versions, the quote does not cover the active TLS session. An attacker who has obtained an enclave TLS private key can relay a genuine quote onto another connection, so a relying party may accept an attacker-controlled connection as the attested enclave. The attacker needs the TLS private key, which is hard to obtain, so the practical risk is limited to deployments that use this product.
Affected
- Privasys Enclave OS (Virtual) before tdx-v0.2.43
- Privasys Enclave OS (Virtual) before tdx-gpu-v0.6.27
- The exact lower boundary of the affected range is unclear; GHSA-p5fp-g94g-g9m9 lists versions up to tdx-v0.2.35 and tdx-gpu-v0.6.26-dev, while other sources state unknown. Treat all versions below the fixed releases as affected.
Fixed in
- tdx-v0.2.43
- tdx-gpu-v0.6.27
Workaround
Unknown. No workaround is documented; the vendor's remedy is to upgrade.
Exploitation
- CISA SSVC: exploitation none, not automatable.
- Not listed in CISA KEV.
- No public exploit or proof of concept known; no exploitation in the wild reported.
Our recommendation
- Check whether Enclave OS (Virtual) or the Privasys forks are in use; if not, no action is needed beyond inventory.
- If in use, upgrade to tdx-v0.2.43 or tdx-gpu-v0.6.27 and check dependency lockfiles.
- After upgrading, check whether enclave TLS keys may have been exposed before the fix and rotate them if so.
- Check the related Privasys rustls and Go fork advisories (CVE-2026-108266, CVE-2026-108267) if those forks are used.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Fix commit 9a6be91 (Privasys/enclave-os-virtual) github.com
- Release tdx-v0.2.43 github.com
- Release tdx-gpu-v0.6.27 github.com
- GitHub Security Advisory GHSA-p5fp-g94g-g9m9 github.com
- Privasys blog: Binding attestation to the TLS session privasys.org
- OSV: CVE-2026-108268 osv.dev
- VulDB entry 416024 vuldb.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 31 Oct 2026, 07:03.
Original description (NVD)
Enclave OS Virtual runs container workloads inside confidential virtual machines with end-to-end attestation. Prior to tdx-v0.2.43 and tdx-gpu-v0.6.27, the TDX/GPU RA-TLS certificate issuer placed the certificate public-key hash and client nonce in quote ReportData but omitted a value bound to the active TLS session. An attacker who obtained an enclave TLS private key could relay a genuine quote onto another connection, causing a relying party to accept an attacker-terminated connection as the attested enclave. This issue is fixed in tdx-v0.2.43 and tdx-gpu-v0.6.27.
NVD references (5)
- https://github.com/Privasys/enclave-os-virtual/commit/9a6be91e29f2b6738d0b77c33cd1ad5cd3d8a347
- https://github.com/Privasys/enclave-os-virtual/releases/tag/tdx-gpu-v0.6.27
- https://github.com/Privasys/enclave-os-virtual/releases/tag/tdx-v0.2.43
- https://github.com/Privasys/enclave-os-virtual/security/advisories/GHSA-p5fp-g94g-g9m9
- https://privasys.org/blog/binding-attestation-to-the-tls-session
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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