CVE-2019-15809
This allows a local attacker, able to measure the duration of hundreds to thousands of signing operations, to compute the private key used.
Does this matter?
Lower severity and a low EPSS score (0.47%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 4.7 MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 0.47% probability · 41th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-203
- Affected
- microchip/atmel toolbox · athena-scs/idprotect · cryptsoft/s\/a idflex v · tecsec/armored card · thalesgroup/etoken 4300
- Source
- cve@mitre.org
EPSS 0.5% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.openwall.com/lists/oss-security/2019/10/02/2Mailing List, Third Party Advisory
- https://csrc.nist.gov/Projects/Cryptographic-Algorithm-Validation-Program/details?source=ECDSA&number=214Third Party Advisory, US Government Resource
- https://eprint.iacr.org/2011/232.pdfTechnical Description, Third Party Advisory
- https://minerva.crocs.fi.muni.cz/Exploit, Third Party Advisory
- https://tches.iacr.org/index.php/TCHES/article/view/7337Technical Description, Third Party Advisory
- https://www.ssi.gouv.fr/certification_cc/bibliotheque-cryptographique-atmel-toolbox-00-03-11-05/Product
- http://www.openwall.com/lists/oss-security/2019/10/02/2Mailing List, Third Party Advisory
- https://csrc.nist.gov/Projects/Cryptographic-Algorithm-Validation-Program/details?source=ECDSA&number=214Third Party Advisory, US Government Resource
- https://eprint.iacr.org/2011/232.pdfTechnical Description, Third Party Advisory
- https://minerva.crocs.fi.muni.cz/Exploit, Third Party Advisory
- https://tches.iacr.org/index.php/TCHES/article/view/7337Technical Description, Third Party Advisory
- https://www.ssi.gouv.fr/certification_cc/bibliotheque-cryptographique-atmel-toolbox-00-03-11-05/Product
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.