CVE-2020-12403

CriticalCVSS 9.1/10Last modified Jun 17, 2026

Description

A flaw was found in the way CHACHA20-POLY1305 was implemented in NSS in versions before 3.55. When using multi-part Chacha20, it could cause out-of-bounds reads. This issue was fixed by explicitly disabling multi-part ChaCha20 (which was not functioning correctly) and strictly enforcing tag length. The highest threat from this vulnerability is to confidentiality and system availability.

Metrics

CVSS 3.1 9.1/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
May 27, 2021
Last modified
Jun 17, 2026
NVD status
Modified

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CVE-2020-12403: Critical severity, CVSS 9.1 | Vulnix