CVE-2020-14933
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 · uneditedcompose.php in SquirrelMail 1.4.22 calls unserialize for the $attachments value, which originates from an HTTP POST request. NOTE: the vendor disputes this because these two conditions for PHP object injection are not satisfied: existence of a PHP magic method (such as __wakeup or __destruct), and any attack-relevant classes must be declared before unserialize is called (or must be autoloaded).
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 confidenceThe compose.php file in SquirrelMail 1.4.22 calls unserialize() on the $attachments parameter which is directly derived from HTTP POST request data. This creates a PHP object injection vulnerability allowing potentially malicious serialized objects to be crafted by an attacker. The vendor disputes severity, claiming no suitable gadget chain (PHP magic methods like __wakeup or __destruct) exists in the codebase.
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= 1.4.22CVSS 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
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/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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Verify SquirrelMail versionLocate and read the SquirrelMail version file (typically VERSION or config/config.php) or check the version reported in the SquirrelMail login footerAffected if The installed version is exactly 1.4.22 (note: only this specific version is affected)
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Locate the compose.php fileFind the compose.php file in the SquirrelMail web root directory (commonly in src/ or the root folder)Affected if The file exists in the expected SquirrelMail installation path
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Inspect unserialize() call on POST dataSearch within compose.php for the pattern unserialize() applied to $_POST['attachments'] or similar POST-derived variable without sanitizationAffected if The code contains unserialize() called directly on POST data without proper validation (vulnerable pattern)
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Confirm attachments POST parameter processingCheck if the application accepts and processes attachments via HTTP POST requests to compose.phpAffected if The attachments parameter from POST requests is processed without sanitization - the attack vector is present
You are affected if you are running SquirrelMail version 1.4.22 AND your compose.php contains an unserialize() call on POST-derived attachment data without input validation.
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 dataReplace unserialize() with json_decode() or implement a strict allowlist via unserialize()'s allowed_classes parameter. Additionally, validate and sanitize all user input before processing. Consider upgrading to a patched version if available.
- Consultation3.0 h
- Implementation4.0 h
- Testing4.0 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 $3,648.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-14933 — 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-2020-14933 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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- 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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