CVE-2026-17520

Newsletters < 4.17 - Insufficient Authorization

2026-08-27 00:00

Strategic Overview

Status: Patched in 4.17
Affected Plugin: Newsletters
Affected Version: < 4.17
CVSS: 5.3Medium
Weakness type: CWE-340 · Generation of Predictable Numbers or Identifiers
CVE: CVE-2026-17520

At a glance

CVE-2026-17520 is a medium-severity Generation of Predictable Numbers or Identifiers vulnerability in the Newsletters WordPress plugin, affecting versions < 4.17. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 4.17; sites on affected versions should update now. Disclosed August 2026, reported by Erwan LR.

Vulnerability Overview

The Newsletters plugin for WordPress is vulnerable to unauthorized access due to insufficient randomization of API keys in all versions up to 4.17 (exclusive). This makes it possible for unauthenticated attackers to access API routes through brute force.

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.

CWE-340: Generation of Predictable Numbers or Identifiers

The product uses a scheme that generates numbers or identifiers that are more predictable than required.

Remediation

Update to version 4.17, or a newer patched version

How does WordSec protect against this?

The fix is the thing that ends this: Newsletters 4.17 closes this, and updating the plugin is the step that ends it.

Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-17520 https://www.wordfence.com/threat-intel/vulnerabilities/id/5958f5ba-523e-496b-b696-2887880203a4 https://nvd.nist.gov/vuln/detail/CVE-2026-17520

Related records

Other vulnerabilities in Newsletters

CVSS Vector

5.3

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityNone
IntegrityLow
AvailabilityNone

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