Fernhill SCADA Uncontrolled Resource Consumption

published 2022-04-12 4 y ago modified 2026-06-17 4 mo ago also EUVD-2022-26400

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 66%
public exploits: 0; none known

A specially crafted packet sent to the Fernhill SCADA Server Version 3.77 and earlier may cause an exception, causing the server process (FHSvrService.exe) to exit.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-22-006-02 updated 2022-01-06 cvss 7.5

Fernhill SCADA

Fernhill Software, Ltd. Fernhill SCADA Server <= 3.77
affected: mitigation “Fernhill recommends users upgrade to Version 3.78 or later.” fernhillsoftware.com

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 18 mo ago (2025-04-16)

Exploit prediction

1.12% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

Fernhill SCADA Server

Classification

Weakness

CWE-400 Uncontrolled Resource Consumption
CWE-755 Improper Handling of Exceptional Conditions

References

cisa.gov /uscert/ics/advisories/icsa-22-006-02
mitigation, third-party-advisory, us-government-resource

Sources

CVE List CVE-2022-21155
NVD CVE-2022-21155

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary