SB2018120638 - Fedora 28 update for nss
Published: December 6, 2018 Updated: April 24, 2025
Security Bulletin ID
SB2018120638
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Cache Attacks (CVE-ID: CVE-2018-12404)
CWE-ID: CWE-300 - Channel Accessible by Non-Endpoint ('Man-in-the-Middle')
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:P/U:Green
The vulnerability allows a remote attacker to perform a downgrade attack on the server and decrypt private keys on the target system.
The vulnerability exists due to a core weakness in TLS that relates to the handshaking of the session key which is used within the tunnel during parallelisation of thousands of oracle queries that occurs using a cluster of TLS servers which share the same public key certificate. A remote attacker can mount a microarchitectural side channel attack against a vulnerable implementation, obtain a network man-in-the-middle position, obtain the relevant data to sign and trigger the victim server to decrypt ciphertexts chosen by the adversary to perform a downgrade attack.
Remediation
Install update from vendor's website.