dbcve.org
Deserialization of Untrusted DataWeakness · CWE-502

CVE-2026-40761

HIGH · 8.1 CVSS v3.1 Published 2026-06-17
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
90/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

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
Unauthenticated PHP Object Injection in Valeska <= 1.2.2 versions.

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 · moderate confidence

Unauthenticated PHP Object Injection vulnerability in Valeska versions 1.2.2 and below allows remote attackers to deserialize untrusted data without proper validation. This type of vulnerability occurs when PHP's unserialize() function is called on user-controlled input, potentially enabling attackers to inject malicious PHP objects that can trigger magic methods to achieve remote code execution or other attacks.

MitigationUpdate Valeska to a version newer than 1.2.2. As an immediate mitigation, review and remove any usage of unserialize() on user-supplied input, replacing with safer alternatives such as JSON encoding/decoding, and implement strict input validation.

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
High
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

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. Confirm Valeska installation and version
    Locate the Valeska application on the system and identify its version number (check version files, headers, or admin interface). Compare the installed version to the affected range: 1.2.2 and below.
    Affected if The installed version is 1.2.2 or lower.
  2. Identify unserialize() usage in application code
    Search the Valeska source code for calls to PHP's unserialize() function. Use grep or similar tools to locate all instances: grep -r "unserialize" /path/to/valeska/
    Affected if Any unserialize() call exists in the application code.
  3. Trace user input to unserialize() calls
    Analyze the identified unserialize() calls to determine if they process data from user-controlled sources (GET/POST parameters, cookies, HTTP headers, or API inputs). Review the data flow from HTTP requests to the unserialize() invocation.
    Affected if User-supplied input (from HTTP requests) is passed directly to unserialize().
  4. Verify absence of input validation or sanitization
    Check whether the data reaching unserialize() undergoes any validation, sanitization, or authentication checks before the unserialize() call. Look for filter functions, validation routines, or authentication gates.
    Affected if User input reaches unserialize() without validation, sanitization, or authentication checks.
  5. Test unauthenticated access to vulnerable endpoint
    If identified, attempt to send a serialized PHP object payload to the affected endpoint without providing authentication credentials. Verify if the application processes the payload.
    Affected if The endpoint accepting serialized data is accessible without authentication.

A user is affected if running Valeska version 1.2.2 or below AND the application contains unserialize() calls that process unauthenticated user input without validation.

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.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update Valeska to a version newer than 1.2.2. As an immediate mitigation, review and remove any usage of unserialize() on user-supplied input, replacing with safer alternatives such as JSON encoding/decoding, and implement strict input validation.

Recommended fix Moderate confidence

Valeska latest version (version > 1.2.2)

  1. 1. Identify the currently installed version of the Valeska plugin/theme
  2. 2. Check if the installed version is <= 1.2.2
  3. 3. Update Valeska to the latest available version from the official source (WordPress repository or vendor)
  4. 4. Verify the update was successful by confirming the new version number
  5. 5. Test the application to ensure normal functionality after the update
Caveat Review changelog for any breaking changes before updating in production environments

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
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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-2026-40761 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
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data