What is CVE-2026-4901?

CVE-2026-4901 is a medium-severity vulnerability in Hydrosystem Control System, classified under Insertion of Sensitive Information into Log File. CVSS score: 6.5/10. Published 2026-04-09.

How severe is CVE-2026-4901?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Information disclosure in Hydrosystem Control System

CVE-2026-4901

AlanWeb SCADA saves sensitive information into a log file. Critically, user credentials are logged allowing the attacker to obtain further authorized access into the system. Combined with vulnerability CVE-2026-34184, these sensitive information could be accessed by an unauthorized user. This issue was fixed in AlanWeb SCADA version 9.8.5

Published 2026-04-09 · last modified 2026-08-13.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.004 (31.8th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 32nd percentile — 31.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001

Affected products

Hydrosystem Control System — versions 0
Hydrosystem.poznan Control System

Weakness classification (CWE)

CWE-532 — Insertion of Sensitive Information into Log File

References

cert.pl/posts/2026/04/CVE-2026-4901/ (Vendor Advisory, third-party-advisory)
www.hydrosystem.poznan.pl/ (Product, product)
control-system.pl/ (product)

Frequently asked questions

What is CVE-2026-4901?: CVE-2026-4901 is a medium-severity vulnerability in Hydrosystem Control System, classified under Insertion of Sensitive Information into Log File. CVSS score: 6.5/10. Published 2026-04-09.
How severe is CVE-2026-4901?: Medium severity. CVSS v3 base score is 6.5 out of 10.