CVE-2019-13629: Matrixssl

Medium severity, CVSS 5.9. EPSS: 1.2% chance of exploitation in the next 30 days.

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.

Affected products

• Matrixssl Matrixssl: up to and including 4.2.1

Published 2019-10-03. Last modified 2026-06-17.