Improper Input ValidationWeakness · CWE-20

CVE-2025-40846

HIGH · 7.1 CVSS v4.0 Published 2025-05-08
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
75/100
Remediation priority · High
Remotely reachable

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Improper Input Validation, the returnUrl parameter in Account Security Settings lacks proper input validation, allowing attackers to redirect users to malicious websites (Open Redirect) and inject JavaScript code to perform cross site scripting attack. The vulnerability affects Halo versions up to 2.174.101 and all versions between 2.175.1 and 2.184.21

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The returnUrl parameter in Halo's Account Security Settings lacks proper input validation, enabling attackers to redirect users to malicious sites (Open Redirect) and inject JavaScript code for Cross-Site Scripting (XSS) attacks.

MitigationImplement strict allowlist-based validation for the returnUrl parameter, restricting it to trusted internal domains/paths, and apply proper output encoding to prevent XSS injection.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
Authentication
Y
User interaction
A
Scope
P

CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:H/VI:L/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:P/AU:Y/R:U/V:X/RE:L/U:Red

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify Halo installation
    Locate the Halo application in your environment and determine its installation method (e.g., look for halo-specific directories, services, or web applications)
    Affected if Halo software is present in the environment
  2. Determine Halo version
    Check the installed version of Halo by examining application metadata, about pages, or version files specific to the installation method
    Affected if The installed version cannot be confirmed as patched or falls within an unpatched version range
  3. Verify Account Security Settings access
    Navigate to or enumerate the Account Security Settings module within the Halo administrative interface
    Affected if The Account Security Settings feature is enabled and accessible to users
  4. Inspect returnUrl parameter handling
    Locate HTTP requests or forms that contain the returnUrl parameter, typically during login, logout, or authentication-related workflows
    Affected if The returnUrl parameter is present in requests and accepts user-controlled input
  5. Test for Open Redirect vulnerability
    Submit a returnUrl value pointing to an external domain (e.g., returnUrl=https://malicious-site.com) and observe if the application redirects users to the untrusted URL
    Affected if The application accepts and redirects to arbitrary external domains without validation
  6. Test for XSS vulnerability
    Submit a returnUrl value containing JavaScript payload (e.g., returnUrl=javascript:alert(1)) and observe if the script executes in the browser
    Affected if The application reflects the returnUrl value without proper encoding, allowing script execution

A user is affected if Halo is installed with an unpatched version and the Account Security Settings feature exposes a returnUrl parameter that permits arbitrary external redirects or unsanitized script injection.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Implement strict allowlist-based validation for the returnUrl parameter, restricting it to trusted internal domains/paths, and apply proper output encoding to prevent XSS injection.

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
14.0 hours of engineering $2,490
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-40846 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
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  • Version or environment caveats, and links to real fixes
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