CVE-2019-15809: Athena-Scs Idprotect

Medium severity, CVSS 4.7. EPSS: 0.5% chance of exploitation in the next 30 days.

Smart cards from the Athena SCS manufacturer, based on the Atmel Toolbox 00.03.11.05 and the AT90SC chip, contain a timing side channel in ECDSA signature generation. This allows a local attacker, able to measure the duration of hundreds to thousands of signing operations, to compute the private key used. The issue occurs because the Atmel Toolbox 00.03.11.05 contains two versions of ECDSA signature functions, described as fast and secure, but the affected cards chose to use the fast version, which leaks the bit length of the random nonce via timing. This affects Athena IDProtect 010b.0352.0005, Athena IDProtect 010e.1245.0002, Athena IDProtect 0106.0130.0401, Athena IDProtect 010e.1245.0002, Valid S/A IDflex V 010b.0352.0005, SafeNet eToken 4300 010e.1245.0002, TecSec Armored Card 010e.0264.0001, and TecSec Armored Card 108.0264.0001.

Affected products

• Athena-Scs Idprotect: version 010b.0352.0005 only; version 010e.1245.0002 only; version 0106.0130.0401 only
• Cryptsoft S/a Idflex V: version 010b.0352.0005 only
• Microchip Atmel Toolbox: version 00.03.11.05 only
• Tecsec Armored Card: version 010e.0264.0001 only; version 108.0264.0001 only
• Thalesgroup Etoken 4300: version 010e.1245.0002 only

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