CVE-2026-3579: Non-constant time multiplication subroutine __muldi3 on RISC-V RV32I
Vulnerability summary
CVE-2026-3579 is a medium (CVSS 5.9) Observable Discrepancy vulnerability in wolfssl. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 19.9% of scored vulnerabilities.
Not severe (CVSS 2.1, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Timeline
- 19-03-2026PublishedVulnerability first disclosed.
- 24-03-2026Last modifiedVulnerability information updated.
Description
wolfSSL 5.8.4 on RISC-V RV32I architectures lacks a constant-time software implementation for 64-bit multiplication. The compiler-inserted __muldi3 subroutine executes in variable time based on operand values. This affects multiple SP math functions (sp_256_mul_9, sp_256_sqr_9, etc.), leading to a timing side-channel that may expose sensitive cryptographic data.
CVSS metrics
7 scores · 5 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated2.1LowCVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N
- NVDNIST2.1LowCVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- OSV · UbuntuEcosystem advisory · calculated5.9MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
- OSV · DebianEcosystem advisory · calculated5.9MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
- OSV · AlpineEcosystem advisory · calculated5.9MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS trend
Probability
0.27%
Chance of exploitation in the next 30 days
Percentile
20%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.27% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
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
- wolfssl< 5.9.0 | 5.8.4
4 vendors · 4 products