Attacker Value
Very Low
(1 user assessed)
Exploitability
Very Low
(1 user assessed)
User Interaction
Unknown
Privileges Required
Unknown
Attack Vector
Unknown
3

CVE-2021-24094

Disclosure Date: February 25, 2021
Add MITRE ATT&CK tactics and techniques that apply to this CVE.
Initial Access
Techniques
Validation
Validated
Lateral Movement
Techniques
Validation
Validated

Description

Windows TCP/IP Remote Code Execution Vulnerability

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5
Ratings
Technical Analysis

This remains a spectacularly new vulnerability with little documentation associated with it beyond Microsoft’s blog here: https://msrc-blog.microsoft.com/2021/02/09/multiple-security-updates-affecting-tcp-ip/
In the blog, this is a remote code execution vulnerability reported as associated with IPv6 packet reassembly. According to the vulnerability report here: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-24094, there is a patch, and you can create a firewall rule on Windows host-based firewalls to block an attack with the command Netsh int ipv6 set global reassemblylimit=0 to block packet reassembly. THIS MAY AFFECT SOME NETWORK TRAFFIC.
A second denial of service vulnerability (CVE-2021-24086) also associated with IPv6 fragment reassembly is mitigated with the same command.
As pure speculation, this vulnerability might be associated with memory corruption through improper length reporting, such that when packets are reassembled in memory, they are placed in a buffer of insufficient size to store them. Should that be the case, this would most likely be a heap vulnerability, and like other heap vulnerabilities before it like eternalblue, bluekeep, and dejablue, it will be a real pain to get to work on a regular basis or as a worm-able exploit.

CVSS V3 Severity and Metrics
Base Score:
None
Impact Score:
Unknown
Exploitability Score:
Unknown
Vector:
Unknown
Attack Vector (AV):
Unknown
Attack Complexity (AC):
Unknown
Privileges Required (PR):
Unknown
User Interaction (UI):
Unknown
Scope (S):
Unknown
Confidentiality (C):
Unknown
Integrity (I):
Unknown
Availability (A):
Unknown

General Information

Additional Info

Technical Analysis