CVE-2020-12403

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.

Category

9.1
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.19%
Vendor Advisory mozilla.org
Affected: n/a nss
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1868931 issue tracking third party advisory patch
https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.55_release_notes release notes vendor advisory
https://lists.debian.org/debian-lts-announce/2023/02/msg00021.html mailing list
https://security.netapp.com/advisory/ntap-20230324-0006/

Frequently Asked Questions

What is the severity of CVE-2020-12403?
CVE-2020-12403 has been scored as a critical severity vulnerability.
How to fix CVE-2020-12403?
To fix CVE-2020-12403, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-12403 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-12403 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-12403?
CVE-2020-12403 affects n/a nss.
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