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 not functioning correctly) and strictly enforcing tag length. The highest threat from this vulnerability is to confidentiality and system availability.
Vulnerability class: Buffer Overflow
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.015 (74.5th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 75th percentile — 74.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.015 · newest: 0.015 · change: 0.000
Affected products
- Mozilla Nss
- Nss — versions nss 3.55
Weakness classification (CWE)
Public proof-of-concept exploits
References
- bugzilla.redhat.com/show_bug.cgi (Patch, Third Party Advisory, Issue Tracking)
- developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.55_release_notes (Release Notes, Vendor Advisory)
- lists.debian.org/debian-lts-announce/2023/02/msg00021.html (mailing-list)
- security.netapp.com/advisory/ntap-20230324-0006/
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.