CVE-2017-9526: Infoleak
In Libgcrypt before 1.7.7, an attacker who learns the EdDSA session key (from side-channel observation during the signing process) can easily recover the long-term secret key. 1.7.7 makes a cipher/ecc-eddsa.c change to store this session key in secure memory, to ensure that constant-time point operations are used in the MPI library.
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is the impact of CVE-2017-9526?
The impact of CVE-2017-9526 is that an attacker can recover long-term secret keys if they learn the EdDSA session key through side-channel attacks during the signing process.
What versions of Libgcrypt are affected by CVE-2017-9526?
Libgcrypt versions prior to 1.7.7 are affected by CVE-2017-9526.
How can I mitigate CVE-2017-9526?
To mitigate CVE-2017-9526, update Libgcrypt to version 1.8.7-6 or later, or 1.10.1-3 or later, or 1.11.0-7 or later.
What changes were made in Libgcrypt to address CVE-2017-9526?
Libgcrypt 1.7.7 introduced changes to store the EdDSA session key in secure memory to prevent side-channel attacks.
Is exploitation of CVE-2017-9526 easy for attackers?
Yes, exploitation of CVE-2017-9526 is relatively easy for attackers who can monitor the signing process.