CVE-2021-43527
9.8 · CRITICALOverview
CVE-2021-43527 is a critical-severity vulnerability affecting mozilla nss. It was published on December 8, 2021 and has a CVSS 3.1 base score of 9.8 (CRITICAL).
This vulnerability has a CVSS 3.1 base score of 9.8, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
NSS (Network Security Services) versions prior to 3.73 or 3.68.1 ESR are vulnerable to a heap overflow when handling DER-encoded DSA or RSA-PSS signatures. Applications using NSS for handling signatures encoded within CMS, S/MIME, PKCS \#7, or PKCS \#12 are likely to be impacted. Applications using NSS for certificate validation or other TLS, X.509, OCSP or CRL functionality may be impacted, depending on how they configure NSS. *Note: This vulnerability does NOT impact Mozilla Firefox.* However, email clients and PDF viewers that use NSS for signature verification, such as Thunderbird, LibreOffice, Evolution and Evince are believed to be impacted. This vulnerability affects NSS < 3.73 and NSS < 3.68.1.
Remediation
Check the references section for vendor advisories and patches from mozilla. Update nss to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| mozilla | nss | >= 0, < 3.73 | Affected |
| mozilla | nss_esr | >= 0, < 3.68.1 | Affected |
| netapp | e-series_santricity_os_controller | 11.0 | Affected |
References
Frequently Asked Questions
What is CVE-2021-43527?
CVE-2021-43527 is a critical-severity vulnerability affecting mozilla nss. It was published on December 8, 2021 and has a CVSS 3.1 base score of 9.8 (CRITICAL).
How severe is CVE-2021-43527?
This vulnerability has a CVSS 3.1 base score of 9.8, rated CRITICAL. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-43527?
Check the references section for vendor advisories and patches from mozilla. Update nss to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-43527?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-43527 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
Automated penetration testing that runs continuously, not just quarterly.
AI-driven PR review catches vulnerable dependencies before they ship.
Browser-based exploitation validates findings with real proof-of-concept.
Related CRITICAL CVEs from 2021
View all →An issue was discovered in the Quiz and Survey Master plugin before 7.0.1 for WordPress. It made it
An issue was discovered in the Ultimate Member plugin before 2.1.12 for WordPress, aka Unauthenticat
An issue was discovered in the Ultimate Member plugin before 2.1.12 for WordPress, aka Unauthenticat
Dell Wyse ThinOS 8.6 and prior versions contain an insecure default configuration vulnerability. A r
Dell Wyse ThinOS 8.6 and prior versions contain an insecure default configuration vulnerability. A r
DELL EMC Avamar Server, versions 19.1, 19.2, 19.3, contain a SQL Injection Vulnerability in Fitness
DELL EMC Avamar Server, versions 19.1, 19.2, 19.3, contain an OS Command Injection Vulnerability in
An improper check for unusual or exceptional conditions in Juniper Networks Junos OS and Junos OS Ev
OneDev is an all-in-one devops platform. In OneDev before version 4.0.3, a Kubernetes REST endpoint
OneDev is an all-in-one devops platform. In OneDev before version 4.0.3, There is a vulnerability th
OneDev is an all-in-one devops platform. In OneDev before version 4.0.3, there is a critical vulnera
OneDev is an all-in-one devops platform. In OneDev before version 4.0.3, AttachmentUploadServlet als