CVE-2026-39554
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 · uneditedUnauthenticated PHP Object Injection in Fidalgo <= 1.2.2 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 confidenceUnauthenticated PHP Object Injection vulnerability in Fidazole plugin/theme versions 1.2.2 and below. The vulnerability allows remote attackers to inject malicious PHP objects via unsanitized user input passed to PHP's unserialize() function, potentially leading to code execution through PHP object gadget chains.
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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:H/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 checksWork through these to decide whether this CVE applies to you.
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Locate Fidazole installation and determine versionCheck the plugin/theme header file (e.g., style.css for themes or main PHP file for plugins) for the 'Version:' field, or query your CMS plugin/theme API if available (WordPress: wp-json/wp/v2/plugins or look in wp-content/plugins/fidalgo directory)Affected if Fidazole version is 1.2.2 or lower, or the version field is missing entirely indicating an older release
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Identify PHP files using unserialize() on user inputSearch the Fidazole directory for 'unserialize(' patterns, particularly in files handling request parameters (GET, POST, COOKIE, orREQUEST superglobals)Affected if Code contains unserialize() calls processing $_GET, $_POST, $_REQUEST, or $_COOKIE without prior sanitization
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Verify the vulnerable entry point is accessibleExamine the identified unserialize() code path to confirm it can be reached without authentication - check for missing capability checks, nonce validations, or login requirements in the surrounding codeAffected if The unserialize() call executes in a code path accessible to unauthenticated users (no is_user_logged_in(), current_user_can(), or auth checks present)
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Check for exposed attack surfaceReview the PHP file containing the vulnerable unserialize() call - note the specific parameter name being processed (e.g., 'data', 'object', 'param')Affected if The vulnerable file handles external input and is directly accessible via web requests (not admin-only)
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Confirm object gadget potential existsReview installed PHP libraries and other plugins/themes on the same system for available gadget chains that could be chained with the injection pointAffected if Additional PHP code with exploitable magic methods (__destruct, __wakeup, __invoke) exists on the system that could be triggered via the injected object
A defender is affected if Fidazole version 1.2.2 or below is installed and the vulnerable unserialize() call handling unauthenticated user input is present and accessible on their system.
Generated from the published advisory. Verify against your own configuration.
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 dataUpgrade to the latest Fidalgo version immediately. If no patched version exists, disable the affected component and implement input validation to prevent untrusted data from reaching PHP deserialization functions.
- Consultation3.0 h
- Implementation6.0 h
- Testing3.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,984.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-39554 — 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 sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-39554 in production — separate from our analysis above.
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
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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.
- 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