Vulnerability in Wolfssl

CVE-2026-3580

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.001 (1.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 1.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-3580: held from 0.001 to 0.001.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: -0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-3580?
CVE-2026-3580 is a medium-severity vulnerability in Wolfssl, classified under Observable Discrepancy. CVSS score: 4.7/10. Published 2026-03-19.
How severe is CVE-2026-3580?
Medium severity. CVSS v3 base score is 4.7 out of 10.