CVE-2026-16257

Arvow AI SEO Writer <= 1.5.3 - Unauthenticated Arbitrary Post Creation via Webhook Secret Type-Juggling

2026-08-05 00:00

Strategic Overview

Status: Patched in 1.5.4
Affected Plugin: Arvow AI SEO Writer
Affected Version: <= 1.5.3
CVSS: 5.3Medium
Weakness type: CWE-862 · Missing Authorization
CVE: CVE-2026-16257

View all Arvow AI SEO Writer vulnerabilities

At a glance

CVE-2026-16257 is a medium-severity Missing Authorization vulnerability in the Arvow AI SEO Writer WordPress plugin, affecting versions <= 1.5.3. 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 1.5.4; sites on affected versions should update now. Disclosed August 2026, reported by Pablo González Pérez.

Vulnerability Overview

The Arvow AI SEO Writer plugin for WordPress is vulnerable to unauthorized access due to a missing capability check on a function in all versions up to, and including, 1.5.3. This makes it possible for unauthenticated attackers to create arbitrary posts.

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-862: Missing Authorization

Reaching this weakness in Arvow AI SEO Writer <= 1.5.3 takes no account at all. A missing authorization check means a function is reachable by anyone who can reach the endpoint, because the code never asks whether the caller is allowed to perform the action.

Any user who can reach the endpoint gets to run an action reserved for higher-privileged roles, from reading protected data to changing settings or content. For Arvow AI SEO Writer the fix is 1.5.4: builds <= 1.5.3 are affected, anything from 1.5.4 onward is not.

Remediation

Update to version 1.5.4, or a newer patched version

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. None of that substitutes for the fix: Arvow AI SEO Writer 1.5.4 closes this, and updating the plugin is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-16257 https://www.wordfence.com/threat-intel/vulnerabilities/id/3ea27f09-30fa-411c-9782-15122ac204d9 https://nvd.nist.gov/vuln/detail/CVE-2026-16257

Related records

Same weakness class

5.3CVE-2026-66469: Arvow AI SEO Writer <= 1.5.3 Missing AuthorizationCVE-2026-66469

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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