---
id: CVE-2026-3416
title: >-
  The API Publisher component previously used a non-cryptographic pseudorandom
  number generator (PRNG) to create shared secrets for Webhook HMAC validation
summary: >-
  The API Publisher component previously used a non-cryptographic pseudorandom
  number generator (PRNG) to create shared secrets for Webhook HMAC validation.
  This PRNG lacks sufficient entropy for security-sensitive operations, allowing
  a s…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-330
vendor: wso2
product: api_control_plane
affected:
  - 'api_control_plane >= 4.5.0, < 4.5.0.53'
  - 'api_manager >= 4.1.0, < 4.1.0.253'
  - 'api_manager >= 4.2.0, < 4.2.0.193'
  - 'api_manager >= 4.3.0, < 4.3.0.104'
  - 'api_manager >= 4.4.0, < 4.4.0.68'
  - 'api_manager >= 4.5.0, < 4.5.0.52'
patched:
  - api_control_plane 4.5.0.53
  - api_manager 4.5.0.52
published: '2026-09-03'
updated: '2026-09-15'
sourceUpdated: '2026-09-15T18:02:04.233'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-3416'
references:
  - url: >-
      https://security.docs.wso2.com/en/latest/security-announcements/security-advisories/2026/WSO2-2026-5174/
    label: ed10eef1-636d-4fbe-9993-6890dfa878f8
tags:
  - nvd
epss: 0.0026
epssPercentile: 0.18108
ingestedAt: '2026-09-15T18:41:59.126Z'
---

## Overview

The API Publisher component previously used a non-cryptographic pseudorandom number generator (PRNG) to create shared secrets for Webhook HMAC validation. This PRNG lacks sufficient entropy for security-sensitive operations, allowing a sophisticated attacker to predict future secrets. This enables malicious actors to forge event payloads with valid HMAC signatures, bypassing the API Gateway's authenticity verification.

Successful exploitation could allow an attacker to predict shared secrets used for Webhook HMAC validation and forge event payloads with valid signatures. This may enable bypassing API Gateway authenticity checks, leading to unauthorized event injection, data manipulation, or downstream system compromise.

## Affected

- `api_control_plane >= 4.5.0, < 4.5.0.53`
- `api_manager >= 4.1.0, < 4.1.0.253`
- `api_manager >= 4.2.0, < 4.2.0.193`
- `api_manager >= 4.3.0, < 4.3.0.104`
- `api_manager >= 4.4.0, < 4.4.0.68`
- `api_manager >= 4.5.0, < 4.5.0.52`

## Remediation

Upgrade past the affected range:

- `api_control_plane 4.5.0.53`
- `api_manager 4.5.0.52`