CVE-2021-38311
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.94%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.94% probability · 59th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-835
- Affected
- contiki-os/contiki
- Source
- cve@mitre.org
References
- https://github.com/contiki-os/contiki/issues/2685Exploit, Issue Tracking, Patch, Third Party Advisory
- https://github.com/contiki-os/contiki/issues/2685Exploit, Issue Tracking, Patch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.