CVE-2026-109516

Bot for Telegram on WooCommerce <= 1.3.0 - Unauthenticated Authentication Bypass to Account Takeover via Fake Telegram Webhook + Brute-Forced Login Token

2026-10-28 14:44
agr0chal

Strategic Overview

Status
Unpatched
Affected Version
<= 1.3.0
CVSS
9.8Critical
Weakness type
CWE-287 · Improper Authentication
CVE
CVE-2026-109516
View all Bot for Telegram on WooCommerce vulnerabilities

At a glance

CVE-2026-109516 is a critical-severity Improper Authentication vulnerability in the Bot for Telegram on WooCommerce WordPress plugin, affecting versions <= 1.3.0. It carries a CVSS score of 9.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. No fixed release has been reported yet; treat installations running this software as exposed. Disclosed October 2026, reported by agr0chal.

Vulnerability Overview

The Bot for Telegram on WooCommerce plugin for WordPress is vulnerable to Authentication Bypass leading to Account Takeover in all versions up to, and including, 1.3.0. The `/wp-json/woo-telegram/v1/main/` REST endpoint is registered with `permission_callback => '__return_true'` and performs no Telegram webhook signature verification, allowing an unauthenticated attacker to POST a forged bot update with a `message.chat.id` set to any WordPress login name; `bftow_get_user_system_id()` resolves this attacker-supplied value to the targeted account via `get_user_by('login', $tgId)` with no ownership proof, and writes a login token computed as `md5($_SERVER['HTTP_USER_AGENT'] . time())` — both inputs are fully attacker-controlled or bounded within seconds using the response's own `Date` header. The resulting token is redeemable at the unauthenticated, capability-check-free, and nonce-less `?action=bftow_create_order&bftow_token=` endpoint, which calls `wp_set_auth_cookie()` unconditionally via `login_user_by_id`, issuing a persistent authenticated session cookie for the targeted account to the attacker. This makes it possible for unauthenticated attackers to log in as any WordPress user, including administrators, given only that user's username.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.

CWE-287: Improper Authentication

Bot for Telegram on WooCommerce <= 1.3.0 carries this weakness at __return_true, and reaching it takes no account at all. Improper authentication means the mechanism that proves who a caller is can be satisfied without the secret it was supposed to require.

An attacker authenticates as another user — administrators included — without ever knowing a password, so password policies and login rate limits never come into play. No fixed build of this plugin is recorded for Bot for Telegram on WooCommerce yet, so installs running <= 1.3.0 stay exposed until the vendor ships one.

Remediation

No known patch available. Please review the vulnerability's details in depth and employ mitigations based on your organization's risk tolerance. It may be best to uninstall the affected software and find a replacement.

How does WordSec protect against this?

This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. No patched version is recorded yet, which is the case where a filtering layer matters most, because there is nothing to update to.

  • Login Security
  • Alerts

External References

Related records

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