CVE-2017-5544

An issue was discovered on FiberHome Fengine S5800 switches V210R240. An unauthorized attacker can access the device's SSH service, using a password cracking tool to establish SSH connections quickly. This will trigger an increase in the SSH login timeout (each of the login attempts will occupy a connection slot for a longer time). Once this occurs, legitimate login attempts via SSH/telnet will be refused, resulting in a denial of service; you must restart the device.

Published: 2017-01-23 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-5544 is rated Moderate Risk (60.6/100): CVSS Medium severity, with high exploitation likelihood (EPSS 5.22%, 91th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +5.19% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

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

Exploit prediction scoring system (EPSS) score for CVE-2017-5544

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 2026-06-15 0.03% 5.22% +5.19%
2 2025-03-17 0.11% 0.03% -0.08%
3 2023-03-07 — 0.11% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-5544

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H 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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.2 3.6 [email protected]
7.1 2.0 HIGH
AV:N/AC:M/Au:N/C:N/I:N/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:C)
Complete availability impact.
 8.6 6.9 [email protected]

Weakness enumeration for CVE-2017-5544

Affected software / configurations for CVE-2017-5544

Vendor Product Version Raw CPE
fiberhome fengine_s5800_firmware v210r240 cpe:2.3:o:fiberhome:fengine_s5800_firmware:v210r240:*:*:*:*:*:*:*

References for CVE-2017-5544

URL Tags
http://www.nfcwar.com URL Repurposed
http://www.securityfocus.com/bid/95708 Third Party Advisory VDB Entry
cvelogic Threat Intelligence