Out-of-bounds Read in Mozilla Nss

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 n…

Vulnerability class: Buffer Overflow

EPSS: 0.015 (72.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2020-12403?
CVE-2020-12403 is a critical-severity vulnerability in Mozilla Nss, classified under Out-of-bounds Read. CVSS score: 9.1/10. Published 2021-05-27.
How severe is CVE-2020-12403?
Critical severity. CVSS v3 base score is 9.1 out of 10.
Is CVE-2020-12403 known to be exploited?
3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.