---
id: "CVE-2026-84918"
kind: "vulnerability"
aliases: ["CVE-2026-84918"]
title: "Drupal Monobank payment API: signature verification flaw allows spoofed signatures"
severity: "low"
cvss: 3.7
epss: 0.00126
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["drupal", "monobank", "package", "payments"]
not_affected_if: ["module-not-installed"]
published_at: "2026-10-22T02:17:02+00:00"
first_seen_at: "2026-10-23T21:57:30+00:00"
updated_at: "2026-10-25T04:43:27+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-84918", "first_seen_at": "2026-10-23T21:57:30+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-84918", "first_seen_at": "2026-10-24T07:15:52+00:00"}]
---

# Drupal Monobank payment API: signature verification flaw allows spoofed signatures

The Drupal Monobank payment API module does not properly verify cryptographic signatures on payment messages. An attacker can forge a signature that the module accepts.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed Monobank payment API module version in the Drupal project (for example with `composer show` or the Drupal extensions page) and see whether it is `1.0.3` or earlier.

## Timeline

- 2026-10-23T21:57:30+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-84918
- 2026-10-24T07:15:52+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-84918

## From the sources

Improper Verification of Cryptographic Signature vulnerability in Drupal Monobank payment API allows Signature Spoof. This issue affects Monobank payment API versions: from 0.0.0 to 1.0.3.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_