High severity · published Aug 21, 2020
CVE-2020-12457
An issue was discovered in wolfSSL before 4.5.0
7.5
CVSS
1.5%
EPSS
No
On KEV
Description
An issue was discovered in wolfSSL before 4.5.0. It mishandles the change_cipher_spec (CCS) message processing logic for TLS 1.3. If an attacker sends ChangeCipherSpec messages in a crafted way involving more than one in a row, the server becomes stuck in the ProcessReply() loop, i.e., a denial of service.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.5% · higher than 75% 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-2020-12457
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-12457
Patch
https://github.com/wolfSSL/wolfssl/pull/2927
Third Party Advisory
https://github.com/wolfSSL/wolfssl/releases/tag/v4.5.0-stable
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