CVE-2020-12457

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.47%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/wolfSSL/wolfssl/pull/2927 third party advisory patch
https://github.com/wolfSSL/wolfssl/releases/tag/v4.5.0-stable third party advisory

Frequently Asked Questions

What is the severity of CVE-2020-12457?
CVE-2020-12457 has been scored as a high severity vulnerability.
How to fix CVE-2020-12457?
To fix CVE-2020-12457, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-12457 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-12457 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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