CVE-2026-3580 Compiler-induced timing leak in sp_256_get_entry_256_9 on RISC-V

Low 2.1 Published 19 Mar 2026 Updated 19 Mar 2026

Compiler optimizations on RISC-V break constant-time ECC operations, allowing local attackers to recover secret keys via timing analysis.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2026-3580?

CVE-2026-3580 is a low-severity vulnerability in Wolfssl Wolfssl, published on 19 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In wolfSSL 5.8.4, constant-time masking logic in sp_256_get_entry_256_9 is optimized into conditional branches (bnez) by GCC when targeting RISC-V RV32I with -O3. This transformation breaks the side-channel resistance of ECC scalar multiplication, potentially allowing a local attacker to recover secret keys via timing analysis.

Weakness: CWE-203

Which versions are affected by CVE-2026-3580?

It affects 1 product.

Products include Wolfssl Wolfssl.

How do I fix CVE-2026-3580?

Apply the vendor's patch.

Is CVE-2026-3580 being exploited?

There is no known exploitation of CVE-2026-3580 in the wild and no public exploit code.

All Wolfssl Wolfssl vulnerabilities

Sources

Also known as DEBIAN-CVE-2026-3580, GHSA-wm74-pvww-q7h2, JLSEC-2026-710, UBUNTU-CVE-2026-3580.