AMD Vitis Libraries CVE-2026-43606

Local process-level access to the same host running the AMD Vitis Libraries ECDSA secp256k1 Security Module is required, consistent with the CVSS 4.0 AV:L rating. The victim application must be actively performing ECDSA signing operations using the secp256k1 curve via the Vitis Libraries Security Module - passive or non-signing workloads are not at risk. For electromagnetic side-channel attacks, physical proximity to the device and specialized measurement equipment are additional prerequisites. Exploitation is limited by: the need to observe many signing operations for statistical key recovery (not a single-request attack), the local-only access vector (no remote unauthenticated path exists), and the requirement for the specific secp256k1 ECDSA code path to be exercised. No authentication bypass or default-configuration exposure applies - this affects only systems actively using the Vitis Libraries cryptographic primitives.

The CVSS 4.0 vector (AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N) scores 8.5, reflecting that local access alone - with no privilege requirement - is sufficient precondition, and that key recovery yields both high confidentiality and integrity impact. However, the local access requirement (AV:L) substantially constrains the real-world threat surface: an attacker must have a process running on the same host or physical proximity for EM analysis, and must be able to observe a sufficient number of ECDSA signing operations to perform statistical key recovery. This is not a trivial one-shot exploit - it requires sustained measurement capability. EPSS data was not provided in the intelligence feed, so exploitation probability cannot be quantified. No CISA KEV listing and no public POC code have been identified, which is consistent with a low-to-moderate near-term exploitation risk. The highest realistic risk is in multi-tenant FPGA research environments, cloud FPGA instances, or any deployment where a less-privileged co-resident process can time or measure cryptographic operations. No conflicting signals were detected between the CVSS vector and the textual description - both consistently indicate local, non-privileged access is the attack surface.

An attacker with a co-resident process on a shared FPGA compute host repeatedly triggers or observes ECDSA secp256k1 signing operations in a victim process using the unpatched Vitis Libraries Security Module. By measuring wall-clock timing differences across thousands of signing calls - exploiting the non-constant-time implementation - the attacker applies a lattice-based key-recovery algorithm to reconstruct the full private key. No public POC has been identified, but this attack class is well-documented in academic literature against non-constant-time ECDSA implementations.