GLSA-202012-21 : Mozilla Network Security Service (NSS): Denial of service

high Nessus Plugin ID 150006
New! Plugin Severity Now Using CVSS v3

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Synopsis

The remote Gentoo host is missing one or more security-related patches.

Description

The remote host is affected by the vulnerability described in GLSA-202012-21 (Mozilla Network Security Service (NSS): Denial of service)

A flaw was found in the way Mozilla Network Security Service (NSS) handled CCS (ChangeCipherSpec) messages in TLS 1.3.
Impact :

A remote attacker could send multiple crafted CSS messages in row after ClientHello message to a server application linked against NSS library, possibly resulting in a Denial of Service condition.
Workaround :

Disable TLS 1.3 protocol.

Solution

All NSS users should upgrade to the latest version:
# emerge --sync # emerge --ask --oneshot --verbose '>=dev-libs/nss-3.58'

See Also

https://security.gentoo.org/glsa/202012-21

Plugin Details

Severity: High

ID: 150006

File Name: gentoo_GLSA-202012-21.nasl

Version: 1.2

Type: local

Published: 5/27/2021

Updated: 6/1/2021

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:gentoo:linux:nss, cpe:/o:gentoo:linux

Required KB Items: Host/local_checks_enabled, Host/Gentoo/release, Host/Gentoo/qpkg-list

Exploit Ease: No known exploits are available

Patch Publication Date: 12/23/2020

Vulnerability Publication Date: 10/20/2020

Reference Information

CVE: CVE-2020-25648

GLSA: 202012-21