Medium severity · published Aug 24, 2020
CVE-2020-24613
wolfSSL before 4.5.0 mishandles TLS 1.3 server data in the WAIT_CERT_CR state, within SanityCheckTls13MsgReceived() in tls13.c
6.8
CVSS
0.9%
EPSS
No
On KEV
Description
wolfSSL before 4.5.0 mishandles TLS 1.3 server data in the WAIT_CERT_CR state, within SanityCheckTls13MsgReceived() in tls13.c. This is an incorrect implementation of the TLS 1.3 client state machine. This allows attackers in a privileged network position to completely impersonate any TLS 1.3 servers, and read or modify potentially sensitive information between clients using the wolfSSL library and these TLS servers.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 58% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WO
Wolfssl · Wolfssl
before 4.5.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-24613
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-24613
Exploit
https://research.nccgroup.com/2020/08/24/technical-advisory-wolfssl-tls-1-3-client-man-in-the-middle-attack/
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