CVE-2021-45098

7.5 HIGH
Published: December 16, 2021 Modified: November 03, 2025

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://forum.suricata.io/t/suricata-6-0-4-and-5-0-8-released/1942
Source: cve@mitre.org
Release Notes Vendor Advisory
https://github.com/OISF/suricata/releases
Source: cve@mitre.org
Release Notes Third Party Advisory
https://redmine.openinfosecfoundation.org/issues/4710
Source: cve@mitre.org
Exploit Issue Tracking Patch Vendor Advisory
https://forum.suricata.io/t/suricata-6-0-4-and-5-0-8-released/1942
Source: af854a3a-2127-422b-91ae-364da2661108
Release Notes Vendor Advisory
https://github.com/OISF/suricata/commit/50e2b973eeec7172991bf8f544ab06fb782b97df
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://github.com/OISF/suricata/releases
Source: af854a3a-2127-422b-91ae-364da2661108
Release Notes Third Party Advisory
https://redmine.openinfosecfoundation.org/issues/4710
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Issue Tracking Patch Vendor Advisory

9 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.5 / 10.0
EPSS (Exploit Probability)
0.6%
70th percentile
Exploitation Status
Not in CISA KEV

Affected Vendors

oisf debian