CVE-2019-18792

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

06/01/2020

Last modified:

22/10/2024

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.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 9.10 CRITICAL
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): High
Availability (A): High

Base Score 3.x

9.10

Severity 3.x

CRITICAL

Vector 2.0

AV:N/AC:L/Au:N/C:N/I:P/A:P CVSS v2.0 Severity and Metrics:

Base Score: 6.40 MEDIUM
Vector: AV:N/AC:L/Au:N/C:N/I:P/A:P

Attack Vector (AV): Network
Attack Complexity (AC): Low
Authentication (Au): None
Confidentiality (C): None
Integrity (I): Physical
Availability (A): Physical

Base Score 2.0

6.40

Severity 2.0

MEDIUM

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:a:oisf:suricata::::::::	4.1.5 (including)	4.1.6 (excluding)
cpe:2.3:a:oisf:suricata:5.0.0:::::::*
cpe:2.3:o:debian:debian_linux:8.0:::::::*

To consult the complete list of CPE names with products and versions, see this page

CVE-2019-18792

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools