dbcve.org
Grand ConferenceWordPress extension · Themegoods

CVE-2025-39354

CRITICAL · 9.8 CVSS v3.1 Published 2025-05-19
Fix available
A fix is available. Upgrade to after 5.3 or later.
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
Deserialization of Untrusted Data vulnerability in ThemeGoods Grand Conference grandconference allows Object Injection.This issue affects Grand Conference: from n/a through <= 5.3.

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

The ThemeGoods Grand Conference WordPress theme contains a deserialization vulnerability where untrusted data is passed to PHP's unserialize() function, allowing attackers to inject arbitrary PHP objects. This can lead to remote code execution, file manipulation, or other attacks depending on available classes in the application.

MitigationReplace unsafe unserialize() calls with json_decode() or other safe deserialization methods, validate all input, and update to a patched version if available. If the theme is abandoned, migrate to an actively maintained alternative.

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

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Grand ConferenceWordPress extension
Affected:<= 5.3

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. Confirm Grand Conference theme is installed
    Check your WordPress installation under wp-content/themes/ for a folder named 'grandconference' or 'grand-conference'. In WordPress admin, go to Appearance > Themes to verify the theme is present and active.
    Affected if The theme folder 'grandconference' exists in wp-content/themes/ and the theme is active in WordPress.
  2. Identify the installed theme version
    Open the theme's style.css file in wp-content/themes/grandconference/ and look for the 'Version:' header in the comment block at the top. Alternatively, check functions.php for a version constant like 'THEMEGO_VERSION' or '$theme_version'.
    Affected if The version number found is 5.3 or lower, or no version is explicitly defined (which may indicate an older unpatched release).
  3. Locate unsafe unserialize() calls in theme files
    Search all PHP files in the theme directory for 'unserialize' patterns. Run: grep -r "unserialize" wp-content/themes/grandconference/ --include="*.php" from your WordPress root, or manually inspect common entry points like functions.php, plugin.php, ajax-handlers, and any file handling serialized data from $_GET, $_POST, $_REQUEST, or database fields.
    Affected if Any PHP file in the theme contains an unserialize() call that processes data from user-controlled sources (request parameters, database content, or external API responses) without prior sanitization.
  4. Verify if the vulnerable deserialization is reachable
    Examine the code around any found unserialize() calls. Determine if the data being deserialized originates from unauthenticated sources such as URL parameters, form inputs, or stored database values that can be modified by lower-privileged users.
    Affected if The unserialize() function receives $_GET, $_POST, $_REQUEST variables, or data from wp_options/get_option calls that could be injected with malicious serialized payloads.

Your environment is affected if the Grand Conference theme is installed with version 5.3 or lower and contains any unserialize() calls processing untrusted input from HTTP requests or database fields.

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
Upgrade available Upgrade to a release after 5.3
Interim mitigation

Replace unsafe unserialize() calls with json_decode() or other safe deserialization methods, validate all input, and update to a patched version if available. If the theme is abandoned, migrate to an actively maintained alternative.

Fix this in Grand Conference Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,980
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,168.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-39354 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2025-39354 in production — separate from our analysis above.

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