VULNERABILITY INTELLIGENCE
CVE-2019-18792
CVSS score9.1 CRITICAL
EPSS probability2.52%
CISA KEVNot currently listed
Published2020-01-06
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Description
An issue was discovered in Suricata 5.0.0. It is possible to bypass/evade any tcp based signature by overlapping a TCP segment with a fake FIN packet. The fake FIN packet is injected just before the PUSH ACK packet we want to bypass. The PUSH ACK packet (containing the data) will be ignored by Suricata because it overlaps the FIN packet (the sequence and ack number are identical in the two packets). The client will ignore the fake FIN packet because the ACK flag is not set. Both linux and windows clients are ignoring the injected packet.
Weakness classification
- CWE-436: Interpretation Conflict
Primary references
- cve@mitre.org — Patch, Third Party Advisory
- cve@mitre.org — Patch, Third Party Advisory
- cve@mitre.org — Third Party Advisory
- cve@mitre.org — Exploit, Third Party Advisory
- cve@mitre.org — Exploit, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Exploit, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Exploit, Third Party Advisory