High severity · published Jan 29, 2021
CVE-2021-3336
DoTls13CertificateVerify in tls13.c in wolfSSL before 4.7.0 does not cease processing for certain anomalous peer behavior (sending an ED22519, ED448, ECC, or RSA signature without…
8.1
CVSS
0.8%
EPSS
No
On KEV
Description
DoTls13CertificateVerify in tls13.c in wolfSSL before 4.7.0 does not cease processing for certain anomalous peer behavior (sending an ED22519, ED448, ECC, or RSA signature without the corresponding certificate). The client side is affected because man-in-the-middle attackers can impersonate TLS 1.3 servers.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 56% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WO
Wolfssl · Wolfssl
before 4.7.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3336
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3336
Patch
https://github.com/wolfSSL/wolfssl/pull/3676
Vendor Advisory
https://www.wolfssl.com/docs/security-vulnerabilities
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