Vulnerability record · CVE-2020-25648 · published 20 October 2020
CVE-2020-25648: Mozilla network security services allocation without limits vulnerability
Mozilla · Network Security Services
A flaw was found in the way NSS handled CCS (ChangeCipherSpec) messages in TLS 1.3. This flaw allows a remote attacker to send multiple CCS messages, causing a denial of service for servers compiled with the NSS library. The highest threat from this vulnerability is to system availability. This flaw affects NSS versions before 3.58.
Description
A flaw was found in the way NSS handled CCS (ChangeCipherSpec) messages in TLS 1.3. This flaw allows a remote attacker to send multiple CCS messages, causing a denial of service for servers compiled with the NSS library. The highest threat from this vulnerability is to system availability. This flaw affects NSS versions before 3.58.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
6 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2020-25648), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.