Deserialization of Untrusted DataWeakness · CWE-502

CVE-2025-0855

CRITICAL · 9.8 CVSS v3.1 Published 2025-05-06

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

NVD · unedited

The PGS Core plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 5.8.0 via deserialization of untrusted input in the 'import_header' function. This makes it possible for unauthenticated attackers to inject a PHP Object. No known POP chain is present in the vulnerable software. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.

Technical summary

dbcve analysis · high confidence

The PGS Core WordPress plugin suffers from PHP Object Injection via unsafe deserialization in the 'import_header' function. Unauthenticated attackers can exploit this to inject arbitrary PHP objects. While the vulnerable plugin itself contains no POP chain, a chain from other installed plugins or themes could enable file deletion, data theft, or code execution.

MitigationUpdate PGS Core to the latest version immediately. If no patched version is available, disable the plugin and audit all other installed plugins and themes for POP chain capabilities that could be chained with this vulnerability.

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

CVSS breakdown

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?

dbcve checks

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

Verify PGS Core plugin installation

In WordPress admin, go to Plugins > Installed Plugins and search for 'PGS Core' or check the file wp-content/plugins/pgs-core/ for existence

Affected if PGS Core plugin is present in the WordPress installation
Check installed PGS Core version

View the plugin file header at wp-content/plugins/pgs-core/pgs-core.php or use wp-cli command: wp plugin list --name=pgs-core --format=json

Affected if Version is older than the latest patched version (compare against the current version on wordpress.org)
Confirm plugin is active

Check WordPress options table for active_plugins option or verify via Plugins > Installed Plugins in admin panel

Affected if PGS Core plugin is active
Verify vulnerable function is accessible

The import_header function handles deserialization - check if the plugin's import functionality is exposed via admin-ajax.php or front-end endpoints. Inspect the plugin source code for the import_header function and its call locations.

Affected if The import_header function is reachable without authentication (unauthenticated access is possible per CVE details)
Audit other plugins/themes for POP chains

Review all installed plugins and themes for classes with magic methods (__wakeup, __destruct, __toString, etc.) that could form a POP chain. Check wp-content/plugins/ and wp-content/themes/ directories.

Affected if Any installed plugin or theme contains exploitable PHP object injection primitives that could be chained with this vulnerability

If PGS Core is installed, active, running an unpatched version, and the import_header function is accessible, the environment is vulnerable to PHP Object Injection via CVE-2025-0855.

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

Remediation

From vendor data

Mitigation available No clean upgrade yet — mitigate in the meantime

Mitigation

Update PGS Core to the latest version immediately. If no patched version is available, disable the plugin and audit all other installed plugins and themes for POP chain capabilities that could be chained with this vulnerability.

Have this fixed Scoped from the published advisory

Consultation2.0 h
Implementation1.0 h
Testing2.0 h
Review / QA1.0 h

6.0 hours of engineering $1,060

Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.

Scan for this in your stack

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References

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-0855 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2025-0855?

The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.

The version that genuinely resolved it — not the one the vendor claimed
A config change or rule that shut the vector down
A gotcha in the upgrade path that cost you an afternoon

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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

At a glance

A fix existsA vendor remedy is published

Severity 9.8 Critical

Exploit likelihood EPSS, next 30 days 0.6%

Remediation

A high-priority fix

Have this fixed 6 hrs · Moderate

Typical engagement from $1,060

Get a fix See the full breakdown ↓

A high-priority vulnerability. Send your environment and a specialist will scope CVE-2025-0855 and return a fixed quote and timeline.

You’ll deal with our team directly and deploy the reviewed fix to staging first — never straight to production.

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.

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.

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.

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.

Check your environment

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.

Scan for this in your stack

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Practitioner notes

No notes yet

Official description

Technical summary

CVSS breakdown

Am I affected?

Remediation

References