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CVE-2026-18143

Critical Vulnerability: CVE-2026-18143

The Request a Quote for WooCommerce plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 2.9.2 via the `afrfq_submit_quote_via_popup()` function. This is due to missing file extension and MIME type validation in the popup upload handler, which uses the raw attacker-supplied filename directly as the destination for `move_uploaded_file()`. This makes it possible for unauthenticated attackers to upload executable files, such as PHP files, to a web-access

Saturday, September 26, 2026Vulnios Threat Intelligence
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Vulnerability Snapshot

CVE-2026-18143 is rated CRITICAL — exploitation is trivial or already observed in the wild and impact is severe. Patch immediately, not on the next maintenance window.

Executive Summary

The Request a Quote for WooCommerce plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 2.9.2 via the afrfq_submit_quote_via_popup() function. This is due to missing file extension and MIME type validation in the popup upload handler, which uses the raw attacker-supplied filename directly as the destination for move_uploaded_file(). This makes it possible for unauthenticated attackers to upload executable files, such as PHP files, to a web-accessible temporary RFQ upload directory when a public quote rule with the multi-page popup flow is enabled.

Why It Matters

CVE-2026-18143 is rated CRITICAL severity, requiring immediate attention from security teams.

CVSS Base Score: 9.8/10

🛡️What Defenders Should Check

  • Check if you are affected — Review your asset inventory for products listed in CVE-2026-18143.
  • Apply available patches — Visit vendor advisories for the latest security updates.
  • Monitor for exploitation — Check your SIEM/IDS logs for related indicators.

    • Use Vulnios to continuously monitor your exposure to CVE-2026-18143 and similar vulnerabilities.

    References & Sources

  • https://woocommerce.com/products/request-a-quote-plugin-for-woocommerce/
  • https://www.wordfence.com/threat-intel/vulnerabilities/id/3417ec27-6abf-45c7-945f-6ef456ba1187?source=cve

    • How Vulnios Detects This

    Vulnios scans for this vulnerability using Trivy and Grype for SBOM-based CVE matching and Vulnios CVE feed continuous monitoring against your asset inventory. Run a scan against your environment to see whether you are exposed; findings are linked back to the original CVE record so triage starts with the patch path already known.

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    Sources

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    Frequently Asked Questions

    What is CVE-2026-18143?

    CVE-2026-18143 is a critical-severity vulnerability tracked under the Common Vulnerabilities and Exposures program. The Request a Quote for WooCommerce plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 2.9.2 via the afrfq_submit_quote_via_popup() function. This is d

    Am I affected?

    Affected technology is listed in the Affected Products section above. If your asset inventory contains any of them, assume in-scope until you can prove otherwise.

    How urgent is the response?

    Critical: do not wait for your normal patch cycle. Verify exposure today, apply the vendor patch immediately, and add detection rules for any post-exploit indicators.

    How do I remediate?

    Apply the vendor patch listed in the upstream advisory linked under Sources. If the patch is not yet available, follow the vendor-supplied workaround (often a config flag or feature disable) and add detections for the published exploit pattern in your SIEM. Re-scan after the patch lands to confirm the finding clears.

    Where can I track exploitation activity?

    Watch CISA's Known Exploited Vulnerabilities catalog for CVE-2026-18143. Cross-reference with public exploit databases and your own SIEM/IDS for indicator-of-compromise patterns. Vulnios tracks KEV status automatically and surfaces it on the asset findings view.

    How does Vulnios help with this?

    Vulnios continuously cross-references your asset inventory against the live CVE feed (NVD, vendor advisories, CISA KEV, and curated OSINT). When a new CVE matches your environment, you get a prioritized finding with the severity, KEV status, exploit-prediction (EPSS), and a direct path to the vendor patch. You can start a free scan from the homepage.

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