SB2024041082 - Ubuntu update for nss
Published: April 10, 2024
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 vulnerabilities.
1) Covert Timing Channel (CVE-ID: CVE-2023-4421)
CWE-ID: CWE-385 - Covert Timing Channel
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to gain access to sensitive information.
The vulnerability exists due to NSS code used for checking PKCS#1 v1.5 was leaking information useful in mounting Bleichenbacher-like attacks. Both the overall correctness of the padding as well as the length of the encrypted message was leaking through timing side-channel. By sending large number of attacker-selected ciphertexts, the attacker would be able to decrypt a previously intercepted PKCS#1 v1.5 ciphertext (for example, to decrypt a TLS session that used RSA key exchange), or forge a signature using the victim's key.
2) Covert timing channel (CVE-ID: CVE-2023-5388)
CWE-ID: CWE-385 - Covert Timing Channel
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to perform MitM attack.
The vulnerability exists due to insufficient fix for #VU84108 (CVE-2023-4421). A remote attacker can perform Marvin attack and gain access to sensitive information.
3) Observable discrepancy (CVE-ID: CVE-2023-6135)
CWE-ID: CWE-203 - Observable discrepancy
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to gain access to sensitive information.
The vulnerability exists due to a side-channel attack in multiple NSS NIST curves, known as "Minerva". A remote attacker can recover the private key and decrypt data passed between server and client.
Remediation
Install update from vendor's website.