CVE-2026-19887
HIGHCVE-2026-19887 is a high-severity (CVSS 8.8) Deserialization of Untrusted Data vulnerability. O3 Security confirms whether CVE-2026-19887 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
The Welcart e-Commerce plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 2.12.1 via deserialization of untrusted input in the Telecom…
Description
The Welcart e-Commerce plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 2.12.1 via deserialization of untrusted input in the Telecom EDY payment callback (usces_action_acting_transaction). Unauthenticated attackers can store arbitrary 'reserve' key/value pairs as order metadata during a public checkout, then invoke the callback with an attacker-chosen 'option' parameter to select and unserialize that metadata without any provider signature, source-address, transaction-identity or ownership check. A POP chain is present in the TCPDF library bundled with the plugin itself, so no additional plugin or theme is required. This makes it possible for unauthenticated attackers to delete arbitrary files on the server, including wp-config.php, which can lead to remote code execution when an attacker re-runs the WordPress installer against a database they control. Successful exploitation is contingent on an admin printing an invoice to trigger file deletion.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-19887 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-19887 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-19887. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-19887 in your dependencies?
O3 detects CVE-2026-19887 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.