Deserialization of Untrusted DataWeakness · CWE-502

CVE-2026-27429

CRITICAL · 9.8 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 →
100/100
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 Nifty <= 1.4.1 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 Nifty versions 1.4.1 and below allows remote attackers to inject malicious PHP objects through insecure deserialization of untrusted input, potentially achieving remote code execution via magic methods.

MitigationUpgrade to a patched version newer than 1.4.1 if available; otherwise, implement strict whitelist-based input validation on all deserialization entry points and replace unserialize() with safer alternatives like JSON decoding.

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

CVSS:3.1/AV:N/AC:L/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. Identify if Nifty software is installed
    Check for the presence of Nifty application files in the web root or document directory. Look for directories or files containing 'nifty' in the name, or check the application's index page for branding that identifies it as Nifty.
    Affected if The Nifty application is present on the server
  2. Determine the installed Nifty version
    Check the application source code for a version file, composer.json, or a configuration file that displays the version number. Common locations include a version.php file, README, or the admin dashboard about page.
    Affected if The installed version is 1.4.1 or below, or the version cannot be determined and the software appears to be Nifty
  3. Locate deserialization code in the application
    Search PHP source files for usage of unserialize() function. Use grep or a file search tool to find 'unserialize' in the application code, particularly in files that handle user input, request parameters, or cookie values.
    Affected if Code contains unserialize() calls that process input from untrusted sources (GET, POST, cookies, or API requests)
  4. Check if deserialization endpoints are exposed without authentication
    Review the identified unserialize() entry points and determine if they are protected by authentication checks. Examine the code surrounding the unserialize calls to see if there are any access control conditions (like session checks, login验证) before the deserialization occurs.
    Affected if The deserialization functionality can be reached by unauthenticated users (no login or session required)
  5. Inspect for magic method usage in the codebase
    Search PHP files for magic method definitions such as __destruct(), __wakeup(), __toString(), or __invoke that could be triggered by injected PHP objects.
    Affected if The application defines magic methods in included PHP classes that could be leveraged for RCE if object injection occurs

A user is affected if they have Nifty version 1.4.1 or below running with unauthenticated deserialization endpoints that use unserialize() on untrusted input.

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

Upgrade to a patched version newer than 1.4.1 if available; otherwise, implement strict whitelist-based input validation on all deserialization entry points and replace unserialize() with safer alternatives like JSON decoding.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing8.0 h
  • Review / QA4.0 h
24.0 hours of engineering $4,160
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Scan for this in your stack

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dbcve dependency scanner

Check whether your project pulls in CVE-2026-27429 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

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-2026-27429 in production — separate from our analysis above.

No notes yet

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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
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