CVE-2021-45098: High severity suricata vulnerability
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.
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is the vulnerability name and ID?
The vulnerability is named CVE-2021-45098.
What is the severity of CVE-2021-45098?
The severity of CVE-2021-45098 is high with a severity value of 7.5.
What software is affected by CVE-2021-45098?
Suricata versions up to and excluding 6.0.4 and Debian Linux versions 9.0, 10.0, and 11.0 are affected by CVE-2021-45098.
Is there a workaround for CVE-2021-45098?
There is currently no known workaround for CVE-2021-45098.
How can I fix CVE-2021-45098?
To fix CVE-2021-45098, upgrade to Suricata version 6.0.4 or later. Additionally, update Debian Linux to a version that includes the fix.