CVE-2026-3204Network attack vector

Error-message spoofing via URL-supplied text

Published Mar 3, 2026 · Updated Mar 3, 2026

Improper input validation in Devolutions Server 2025.3.16 and earlier allows remote attackers to spoof errors via crafted URLs. The error message page renders message text supplied directly in the URL instead of selecting server-defined text from a validated error code. No authentication is required, but user interaction is required for the displayed text to support phishing or other content-spoofing attacks.

CVSS severity5.1
Medium
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Devolutions Server 2025.3.16 and earlier allows remote attackers to spoof errors via crafted URLs. The error message page renders message text supplied directly in the URL instead of selecting server-defined text from a validated error code. No authentication is required, but user interaction is required for the displayed text to support phishing or other content-spoofing attacks.

The record

CVE
CVE-2026-3204
Published
Mar 3, 2026
Updated
Mar 3, 2026
Vendor
Ironman Software
Product
Devolutions Server
Classifications
CWE-20, T1566.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 3, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <2025.3.16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Ironman Software · Devolutions Serverversion=0 <2025.3.16

Published CVSS scores

5.1DevolutionsCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1566.002Spearphishing Link

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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