CVE-2021-45098

high

Description

An issue was discovered in Suricata before 6.0.4. It is possible to bypass/evade any HTTP-based signature by faking an RST TCP packet with random TCP options of the md5header from the client side. After the three-way handshake, it's possible to inject an RST ACK with a random TCP md5header option. Then, the client can send an HTTP GET request with a forbidden URL. The server will ignore the RST ACK and send the response HTTP packet for the client's request. These packets will not trigger a Suricata reject action.

References

https://redmine.openinfosecfoundation.org/issues/4710

https://github.com/OISF/suricata/releases

https://github.com/OISF/suricata/commit/50e2b973eeec7172991bf8f544ab06fb782b97df

https://forum.suricata.io/t/suricata-6-0-4-and-5-0-8-released/1942

Details

Source: Mitre, NVD

Published: 2021-12-16

Updated: 2024-11-21

Risk Information

CVSS v2

Base Score: 5

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

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:H/A:N

Severity: High