MatrixSSL 4.2.1 and earlier contains a timing side channel in ECDSA signature generation. This allows a local or a remote attacker, able to measure the duration of hundreds to thousands of signing operations, to compute the private key used. The issue occurs because crypto/pubkey/ecc_math.c scalar multiplication leaks the bit length of the scalar.
Conclusion & alert: CVE-2019-13629 is rated Moderate Risk (47.4/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.24%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.27% | 1.24% | +0.97% |
| 2 | 2025-11-21 | 0.23% | 0.27% | +0.05% |
| 3 | 2025-11-18 | — | 0.23% | — |
Full EPSS history (12 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.9 | 3.1 | MEDIUM |
|
2.2 | 3.6 | [email protected] |
| 4.3 | 2.0 | MEDIUM |
|
8.6 | 2.9 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
ubuntu
|
low | CVE-2019-13629 low priority: Ubuntu including 1 source packages (matrixssl), 5 status rows across 5 suites (bionic, disco, trusty, upstream, xenial): DNE 4, needs-triage 1. | https://ubuntu.com/security/CVE-2019-13629 |
| URL | Tags |
|---|---|
| http://www.openwall.com/lists/oss-security/2019/10/02/2 | Mailing List Third Party Advisory |
| https://eprint.iacr.org/2011/232.pdf | Not Applicable |
| https://minerva.crocs.fi.muni.cz/ | Product |
| https://tches.iacr.org/index.php/TCHES/article/view/7337 | Not Applicable |