CVE-2018-0495: Infoleak
An implementation flaw was discovered in multiple cryptographic libraries that allows a side-channel based attacker to recover ECDSA or DSA private keys. When these cryptographic libraries use the private key to create a signature, such as for a TLS or SSH connection, they inadvertently leak information through memory caches. An unprivileged attacker running on the same machine can collect the information from a few thousand signatures and recover the value of the private key.
External References:
https://www.nccgroup.trust/us/our-research/technical-advisory-return-of-the-hidden-number-problem/
Other sources
Libgcrypt before 1.7.10 and 1.8.x before 1.8.3 allows a memory-cache side-channel attack on ECDSA signatures that can be mitigated through the use of blinding during the signing process in the gcryeccecdsasign function in cipher/ecc-ecdsa.c, aka the Return Of the Hidden Number Problem or ROHNP. To discover an ECDSA key, the attacker needs access to either the local machine or a different virtual machine on the same physical host.
Affected Software
Remediation
Patch Available
Event History
Parent advisories
This vulnerability appears in the following advisories.
Frequently Asked Questions
What is the severity of CVE-2018-0495?
CVE-2018-0495 is rated as high severity due to the potential for private key recovery through a side-channel attack.
How do I fix CVE-2018-0495?
To mitigate CVE-2018-0495, update to the fixed versions of the affected packages listed in the vulnerability report.
Which software is affected by CVE-2018-0495?
CVE-2018-0495 affects several cryptographic libraries including jbcs-httpd24-httpd and jbcs-httpd24-openssl among others.
What type of attack does CVE-2018-0495 enable?
CVE-2018-0495 enables a side-channel attack that can lead to the recovery of ECDSA or DSA private keys.
Is CVE-2018-0495 limited to specific operating systems?
CVE-2018-0495 affects multiple operating systems, including various versions of Red Hat Enterprise Linux and Debian.