CVE-2020-17469

high

Description

An issue was discovered in FNET through 4.6.4. The code for IPv6 fragment reassembly tries to access a previous fragment starting from a network incoming fragment that still doesn't have a reference to the previous one (which supposedly resides in the reassembly list). When faced with an incoming fragment that belongs to a non-empty fragment list, IPv6 reassembly must check that there are no empty holes between the fragments: this leads to an uninitialized pointer dereference in _fnet_ip6_reassembly in fnet_ip6.c, and causes Denial-of-Service.

References

https://www.tenable.com/blog/amnesia33-researchers-disclose-33-vulnerabilities-tcpip-libraries-uip-fnet-picotcp-nutnet

https://www.kb.cert.org/vuls/id/815128

https://us-cert.cisa.gov/ics/advisories/icsa-20-343-01

http://fnet.sourceforge.net/manual/fnet_history.html

Details

Source: Mitre, NVD

Published: 2020-12-11

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

Severity: Medium

CVSS v3

Base Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High