CVE-2021-40523
7.5 HIGHIn Contiki 3.0, Telnet option negotiation is mishandled
Published: 2021-09-05 · Last updated: 2026-06-17
Severity and scoring
- CVSS
- 7.5 HIGH
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CWE
- CWE-754
Affected products
| Vendor | Product |
|---|---|
| contiki-os | contiki |
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.
Source: NVD
References
Related CVEs
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- CVE-2021-38387 — In Contiki 3.0, a Telnet server that silently quits (before disconnection with clients) leads to connected clients entering an infinite l... (7.5 HIGH)
- CVE-2021-38386 — In Contiki 3.0, a buffer overflow in the Telnet service allows remote attackers to cause a denial of service because the ls command is mi... (7.5 HIGH)
- CVE-2021-38311 — In Contiki 3.0, potential nonterminating acknowledgment loops exist in the Telnet service (7.5 HIGH)
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