SB2018070223 - Fedora 27 update for botan2
Published: July 2, 2018 Updated: April 24, 2025
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Memory-cache side-channel attack (CVE-ID: CVE-2018-0495)
CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/U:Clear
The vulnerability allows a local attacker to obtain potentially sensitive information.
The vulnerability exists due to a leakage of information through memory caches when the affected library uses a private key to create Elliptic Curve Digital Signature Algorithm (ECDSA) signatures. A local attacker can conduct a memory-cache side-channel attack on ECDSA signatures and recover sensitive information, such as ECDSA private keys, which could be used to conduct further attacks.
Note: The vulnerability is known as the "Return Of the Hidden Number Problem" or ROHNP.
2) Information disclosure (CVE-ID: CVE-2018-12435)
CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local attacker to obtain potentially sensitive information.
The vulnerability exists in the Botan library due to a leakage of information through memory caches when the library uses a private key to create Elliptic Curve Digital Signature Algorithm (ECDSA) signatures as demonstrayed in the dsa/dsa.cpp, ec_group/ec_group.cpp, and ecdsa/ecdsa.cpp source code files. A local attacker can conduct a memory-cache side-channel attack and recover sensitive information, such ECDSA private keys, which could be used to conduct further attacks.
Remediation
Install update from vendor's website.