CVE-2018-6794

Exp

Suricata before 4.0.4 is prone to an HTTP detection bypass vulnerability in detect.c and stream-tcp.c. If a malicious server breaks a normal TCP flow and sends data before the 3-way handshake is complete, then the data sent by the malicious server will be accepted by web clients such as a web browser or Linux CLI utilities, but ignored by Suricata IDS signatures. This mostly affects IDS signatures for the HTTP protocol and TCP stream content; signatures for TCP packets will inspect such network traffic as usual.

Published: 2018-02-07 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-6794 is rated High Exploit Risk (68.6/100): CVSS Medium severity, with high exploitation likelihood (EPSS 37.43%, 97th percentile). 2 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2018-6794

EDB-ID Source Kind Published Link
44247 exploit_db edb 2018-03-05 Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2018-6794

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-11-21 39.01% 37.43% -1.58%
2 2025-11-18 37.43% 39.01% +1.58%
3 2025-09-01 — 37.43% —

Full EPSS history (16 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-6794

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.0 MEDIUM
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2018-6794

OS Trackers for CVE-2018-6794

vendor priority summary link
debian not yet assigned CVE-2018-6794 not yet assigned priority: Debian including 1 source packages (suricata), 4 status rows across 4 suites (bullseye, forky, sid, trixie): resolved 4. https://security-tracker.debian.org/tracker/CVE-2018-6794
ubuntu medium CVE-2018-6794 medium priority: Ubuntu including 1 source packages (suricata), 20 status rows across 20 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 8, DNE 5, ignored 4, needed 2, released 1. https://ubuntu.com/security/CVE-2018-6794

Affected software / configurations for CVE-2018-6794

Vendor Product Version Raw CPE
suricata-ids suricata < 4.0.4 cpe:2.3:a:suricata-ids:suricata:*:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*

References for CVE-2018-6794

cvelogic Threat Intelligence