CVE-2021-43527: exploitation status and patch state
CVE-2021-43527 · CVSS 9.8 CRITICAL · EPSS 18%
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.
Is CVE-2021-43527 exploited?
Not in the CISA KEV catalog.
EPSS puts exploitation in the next 30 days at 18%.
Public exploit code: none found in monitored sources.