Vulnerability in Butok Fnet

CVE-2020-17469

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.

EPSS: 0.030 (85.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

  • cve@mitre.org (US Government Resource, Third Party Advisory, x_refsource_MISC)
  • cve@mitre.org (US Government Resource, Third Party Advisory, x_refsource_MISC)
  • cve@mitre.org (x_refsource_CONFIRM, Third Party Advisory, Release Notes)

Frequently asked questions

What is CVE-2020-17469?
CVE-2020-17469 is a high-severity vulnerability in Butok Fnet, classified under Access of Uninitialized Pointer. CVSS score: 7.5/10. Published 2020-12-11.
How severe is CVE-2020-17469?
High severity. CVSS v3 base score is 7.5 out of 10.