CVSS 3.1
7.5 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:NCVE-2021-45098
High (7.5). EPSS 2.0% chance of exploitation in the next 30 days.
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.
Severity
- EPSS
- 2.0% chance of exploitation in the next 30 days; higher than 80% of CVEs (scores of 2026-10-31)
- Published
- Modified
- Record from
- the NVD, synced
Affected
- debian:debian_linux
- oisf:suricata
References
- https://forum.suricata.io/t/suricata-6-0-4-and-5-0-8-released/1942
- https://github.com/OISF/suricata/commit/50e2b973eeec7172991bf8f544ab06fb782b97df
- https://github.com/OISF/suricata/releases
- https://redmine.openinfosecfoundation.org/issues/4710
- https://forum.suricata.io/t/suricata-6-0-4-and-5-0-8-released/1942