Deserialization of Untrusted DataWeakness · CWE-502

CVE-2026-46725

CRITICAL · 9.2 CVSS v4.0 Published 2026-05-19
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
The extension passes an attacker-controlled cookie directly to PHP's unserialize() without safely processing the input. A remote, unauthenticated attacker can supply a crafted serialized payload to trigger PHP Object Injection, leading to Remote Code Execution on the TYPO3 server. Exploitation requires the content element to be configured with "Persistent Mode: Static" in the plugin settings.

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

A TYPO3 extension vulnerability allows remote attackers to inject PHP objects by supplying a crafted serialized payload through an attacker-controlled cookie. The cookie value is passed directly to PHP's unserialize() function without any sanitization or validation, enabling PHP Object Injection that can lead to arbitrary code execution on the server.

MitigationDisable the 'Persistent Mode: Static' setting in the affected plugin, or apply the vendor patch to replace the unsafe unserialize() call with a secure deserialization method like json_decode().

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
Authentication
X
User interaction
None
Scope
X

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/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:X/AU:X/R:X/V:X/RE:X/U:X

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 the vulnerable TYPO3 extension
    Review your TYPO3 installation for extensions that handle serialized data from cookies and use PHP's unserialize() function. Check extension PHP files for patterns like unserialize($_COOKIE or similar cookie-based deserialization.
    Affected if An extension processes cookie values through unserialize() without validation
  2. Locate plugin settings with Persistent Mode
    Access the TYPO3 backend and navigate to the content elements or plugin configurations. Look for any plugin or content element that has a setting named 'Persistent Mode' set to 'Static' or similar options.
    Affected if Any content element has 'Persistent Mode: Static' enabled in its plugin settings
  3. Verify cookie handling in the extension
    Examine the extension's PHP code that handles cookie values. Look for code paths where cookie data flows directly into unserialize() calls without prior sanitization or use of secure alternatives like json_decode.
    Affected if Cookie values are passed directly to unserialize() without validation

Your environment is affected if a TYPO3 extension processes cookie values through unsafe unserialize() AND any content element has 'Persistent Mode: Static' enabled, allowing remote code execution.

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

Disable the 'Persistent Mode: Static' setting in the affected plugin, or apply the vendor patch to replace the unsafe unserialize() call with a secure deserialization method like json_decode().

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing4.0 h
  • Review / QA2.0 h
13.0 hours of engineering $2,280
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Scan for this in your stack

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dbcve dependency scanner

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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-2026-46725 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
  • No weaponised exploit code, or anything meant to cause harm
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