4.7

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

Analyzed
AliasesUBUNTU-CVE-2026-3580DEBIAN-CVE-2026-3580ALPINE-CVE-2026-3580
Published 19-03-2026Last modified 19-03-2026

Vulnerability summary

CVE-2026-3580 is a medium (CVSS 4.7) Observable Discrepancy vulnerability in wolfssl. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2.8% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 2.1, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
4.7/10
010
Medium · v3.1 (NVD)
EPSS score
0.13%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 19-03-2026
    PublishedVulnerability first disclosed.
  2. 19-03-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

7 scores · 5 sources · 2 versions

EPSS trend

Probability

0.13%

Chance of exploitation in the next 30 days

Percentile

3%

Versus all other CVEs

30-day change

Increase +0.01 pp

From 0.12% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: local access, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Alpine1 product
  • wolfssl< 5.9.1-r0 | < 5.9.0-r0
Debian1 product
  • wolfsslAll versions (No fix recorded)
Ubuntu1 product
  • wolfsslAll versions (No fix recorded)
Wolfssl1 product

4 vendors · 4 products

References

5 links