Buffer overflow in Mozilla Nss
CVE-2021-43527
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.176 (97.1th percentile), scored .
Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 97th percentile — 97.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.176 · newest: 0.176 · change: 0.000
Affected products
- Mozilla Nss — versions unspecified
- Mozilla Nss Esr
- NetApp Cloud Backup
- NetApp E-Series Santricity OS Controller
- Oracle Communications Cloud Native Core Binding Support Function — versions 1.11.0
- Oracle Communications Cloud Native Core Network Repository Function — versions 1.15.0, 1.15.1
- Oracle Communications Cloud Native Core Network Slice Selection Function — versions 1.8.0
- Oracle Communications Policy Management — versions 12.6.0.0.0
- Starwindsoftware Starwind San \& Nas — versions v8r13
- Starwindsoftware Starwind Virtual San — versions v8r13
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.mozilla.org/security/advisories/mfsa2021-51/ (Vendor Advisory)
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking, Vendor Advisory)
- ftp.mozilla.org/pub/security/nss/releases/NSS_3_73_RTM/ (Vendor Advisory)
- ftp.mozilla.org/pub/security/nss/releases/NSS_3_68_1_RTM/ (Vendor Advisory)
- www.oracle.com/security-alerts/cpuapr2022.html (Patch, Third Party Advisory)
- security.netapp.com/advisory/ntap-20211229-0002/ (Third Party Advisory)
- cert-portal.siemens.com/productcert/pdf/ssa-594438.pdf (Third Party Advisory)
- www.starwindsoftware.com/security/sw-20220802-0001/ (Third Party Advisory)
- security.gentoo.org/glsa/202212-05 (vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-43527?
- CVE-2021-43527 is a critical-severity vulnerability in Mozilla Nss, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2021-12-08.
- How severe is CVE-2021-43527?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2021-43527 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.