{"cve":"CVE-2021-45098","nvd":{"published":"2021-12-16T05:15:08.727","modified":"2026-06-17T04:13:10.223","status":"Modified","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","score":7.5},"cwes":[],"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"],"products":["debian:debian_linux","oisf:suricata"],"source":"nvd","synced_at":"2026-10-19T21:25:41.256909649+00:00"},"epss":{"cve":"CVE-2021-45098","score":0.01961,"percentile":0.80319,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}