Deserialization of Untrusted DataWeakness · CWE-502

CVE-2026-49768

CRITICAL · 9.8 CVSS v3.1 Published 2026-06-15
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 Happyforms <= 1.26.13 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 Happyforms WordPress plugin versions 1.26.13 and below. Attackers can exploit unsafe PHP unserialize() calls without authentication to potentially achieve remote code execution via malicious serialized objects.

MitigationUpdate Happyforms plugin to version newer than 1.26.13; if immediate update is not possible, consider disabling the plugin or implementing WAF rules to block serialized object payloads.

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. Confirm Happyforms plugin is installed
    Go to WordPress admin > Plugins and look for 'Happyforms' in the installed plugins list, or check via wp-cli: wp plugin list --name=happyforms
    Affected if Happyforms plugin is not installed or is not active
  2. Check installed Happyforms version
    In WordPress admin > Plugins, click on Happyforms to view version details, or run: wp plugin list --name=happyforms --format=json
    Affected if Version is 1.26.13 or lower
  3. Identify exposed form submission endpoints
    Review site for Happyforms shortcodes or look for forms in wp-admin > Happyforms > Forms, note any public-facing form URLs
    Affected if Public forms exist that accept user input
  4. Inspect server logs for serialized data submissions
    Search access logs for requests to Happyforms endpoints containing patterns like 'O:','a:','s:' (PHP serialized object/array/string markers), e.g., grep -r 'O:%' /var/log/apache2/ or check WAF/IPS logs
    Affected if Logs show incoming requests with serialized PHP data to Happyforms endpoints

You are affected if Happyforms plugin version 1.26.13 or below is installed and active with a public-facing form endpoint that accepts user submissions.

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 Happyforms plugin to version newer than 1.26.13; if immediate update is not possible, consider disabling the plugin or implementing WAF rules to block serialized object payloads.

Recommended fix Moderate confidence

Happyforms version 1.26.14 or later

  1. Log in to the WordPress admin dashboard
  2. Navigate to Plugins > Installed Plugins
  3. Locate Happyforms in the plugin list
  4. Click 'Update now' if an update is available, or manually download the latest version from wordpress.org and upload it
  5. After updating, verify the plugin is running version 1.26.14 or higher by checking the Plugins page
Caveat Minor version patch updates typically contain only bug/security fixes with no expected breaking changes

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

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

Free · runs locally
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-2026-49768 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
  • No spam, self-promotion, credentials, or personal data