CVE-2021-40523

Description

In Contiki 3.0, Telnet option negotiation is mishandled. During negotiation between a server and a client, the server may fail to give the WILL/WONT or DO/DONT response for DO and WILL commands because of improper handling of exception condition, which leads to property violations and denial of service. Specifically, a server sometimes sends no response, because a fixed buffer space is available for all responses and that space may have been exhausted.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.33%
Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/contiki-os/contiki/issues/2686 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-40523?
CVE-2021-40523 has been scored as a high severity vulnerability.
How to fix CVE-2021-40523?
To fix CVE-2021-40523, 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-2021-40523 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-40523 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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