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Critical

Unrestricted File Upload in Contact Form 7 for WordPress

IdentifiersCVE-2020-35489CWE-434· Unrestricted Upload of File with…

CVE-2020-35489 is an unrestricted file upload vulnerability in the Contact Form 7 WordPress plugin before version 5.3.2. According to the provided content, the flaw allows a filename to contain special characters, resulting in insufficient validation of uploaded files. This can permit an attacker to upload arbitrary files, including potentially executable server-side payloads, leading to remote code execution under vulnerable server configurations.

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For your environment

Are you exposed to this one?

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows an attacker to upload arbitrary files to the target WordPress server. If the uploaded file is interpreted as executable code by the web server or application stack, this can result in remote code execution. Depending on server configuration and plugin deployment, this may enable full compromise of the affected WordPress instance, unauthorized access to hosted data, persistence via webshells, and follow-on attacks against the underlying environment.

Mitigation

If you can’t patch tonight, do this now.

Until patching is completed, restrict or disable file upload functionality exposed by the plugin where operationally feasible. Enforce server-side controls that prevent execution of uploaded files in web-accessible upload directories, and ensure web server configuration does not allow script execution from user-upload locations. Additional defensive monitoring of upload paths and WordPress AJAX/file-handling activity can help detect exploitation attempts.

Remediation

Patch, then assume compromise.

Update the Contact Form 7 plugin to version 5.3.2 or later, as the provided content states the issue was patched in version 5.3.2. Verify that no untrusted files were uploaded prior to patching, inspect upload directories for webshells or anomalous files, and remove any malicious artifacts discovered during review.
PUBLIC EXPLOITS

Exploits

No valid public exploits. Mallory filtered out 3 candidates as fakes, detection scripts, or README-only repos.

VALID 0 / 3 TOTALView more in app

All candidate exploits were filtered out by Mallory's validation.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
RocklobsterContact Form 7application

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware1

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity

Community discussion across Reddit, Mastodon, and other social sources.