CVE-2021-40523 — HIGH (7.5)

Vulnerability 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.

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

NONE

Availability

HIGH

Affected Products

Vendor	Product	Versions
Contiki-Os	Contiki	3.0

Related Weaknesses (CWE)

CWE-754

References

https://github.com/contiki-os/contiki/issues/2686PatchThird Party Advisory
https://github.com/contiki-os/contiki/issues/2686PatchThird Party Advisory

FAQ

What is CVE-2021-40523?

CVE-2021-40523 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 becaus...

How severe is CVE-2021-40523?

CVE-2021-40523 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2021-40523?

Check the references section above for vendor advisories and patch information. Affected products include: Contiki-Os Contiki.