// For flags

CVE-2019-18792

 

Severity Score

9.1
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

2
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

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.

Se descubrió un problema en Suricata versión 5.0.0. Es posible omitir y evadir cualquier firma basada en TCP mediante la superposición de un segmento TCP con un paquete FIN falso. El paquete FIN falso es inyectado justo antes del paquete PUSH ACK que queremos omitir. Suricata ignorará el paquete PUSH ACK (que contiene los datos) porque se superpone al paquete FIN (la secuencia y el número ack son idénticos en los dos paquetes). El cliente ignorará el paquete FIN falso porque el flag ACK no está configurado. Tanto los clientes de Linux y Windows ignoran el paquete inyectado.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
Partial
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2019-11-06 CVE Reserved
  • 2020-01-06 CVE Published
  • 2024-05-01 EPSS Updated
  • 2024-08-05 CVE Updated
  • 2024-08-05 First Exploit
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
CWE
  • CWE-436: Interpretation Conflict
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Suricata-ids
Search vendor "Suricata-ids"
Suricata
Search vendor "Suricata-ids" for product "Suricata"
>= 4.1.5 < 4.1.6
Search vendor "Suricata-ids" for product "Suricata" and version " >= 4.1.5 < 4.1.6"
-
Affected
Suricata-ids
Search vendor "Suricata-ids"
Suricata
Search vendor "Suricata-ids" for product "Suricata"
5.0.0
Search vendor "Suricata-ids" for product "Suricata" and version "5.0.0"
-
Affected
Debian
Search vendor "Debian"
Debian Linux
Search vendor "Debian" for product "Debian Linux"
8.0
Search vendor "Debian" for product "Debian Linux" and version "8.0"
-
Affected