2021-38311 | Contiki Telnet Service infinite loop
|CVSS Meta Temp Score
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|CTI Interest Score
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A vulnerability classified as problematic was found in Contiki 3.0. Affected by this vulnerability is an unknown functionality of the component Telnet Service. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-835. As an impact it is known to affect availability. The summary by CVE is:
In Contiki 3.0, potential nonterminating acknowledgment loops exist in the Telnet service. When the negotiated options are already disabled, servers still respond to DONT and WONT requests with WONT or DONT commands, which may lead to infinite acknowledgment loops, denial of service, and excessive CPU consumption.
The weakness was presented 08/10/2021. The advisory is shared at github.com. This vulnerability is known as CVE-2021-38311 since 08/09/2021. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn’t need any form of authentication. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.
There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.
VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.3
Status: Not defined
0-Day Time: 🔒
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