Yubico YubiKey 5 Series devices with firmware before 5.7.0 and YubiHSM 2 devices with firmware before 2.4.0 allow an ECDSA secret-key extraction attack (that requires physical access and expensive equipment) in which an electromagnetic side channel is present because of a non-constant-time modular inversion for the Extended Euclidean Algorithm, aka the EUCLEAK issue. Other uses of an Infineon cryptographic library may also be affected.
The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor, which exposes security-relevant information about the state of the product, such as whether a particular operation was successful or not.
| Link | Tags |
|---|---|
| https://www.yubico.com/support/security-advisories/ysa-2024-03/ | vendor advisory |
| https://support.yubico.com/hc/en-us/articles/15705749884444 | mitigation third party advisory |
| https://ninjalab.io/eucleak/ | third party advisory |
| https://ninjalab.io/wp-content/uploads/2024/09/20240903_eucleak.pdf | technical description |
| https://news.ycombinator.com/item?id=41434500 | issue tracking |
| https://arstechnica.com/security/2024/09/yubikeys-are-vulnerable-to-cloning-attacks-thanks-to-newly-discovered-side-channel/ | press/media coverage |