CVE-2020-12403

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.

• CWE-125
• CWE-125

• https://bugzilla.redhat.com/show_bug.cgi?id=1868931Issue Tracking, Patch, Third Party Advisory
• https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.55_release_notesRelease Notes, Vendor Advisory
• https://lists.debian.org/debian-lts-announce/2023/02/msg00021.html
• https://security.netapp.com/advisory/ntap-20230324-0006/
• https://bugzilla.redhat.com/show_bug.cgi?id=1868931Issue Tracking, Patch, Third Party Advisory
• https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.55_release_notesRelease Notes, Vendor Advisory
• https://lists.debian.org/debian-lts-announce/2023/02/msg00021.html
• https://security.netapp.com/advisory/ntap-20230324-0006/

Published

May 27, 2021

Last Modified

Jun 17, 2026

Status

Modified

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