Security Resilience

CVE-2023-28121

Auth Bypass in Automattic Woocommerce Payments 4.8.0 – 4.8.2

High EPSSAuth Bypass
Published
12 April 2023
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.87 99.7th percentile
Risk Priority 97 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-28121 is a critical-severity Improper Authentication (CWE-287) vulnerability in Automattic Woocommerce Payments. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 0.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

The vulnerability CVE-2023-28121 is an improper authentication flaw (CWE-287) in the WooCommerce Payments plugin for WordPress, affecting all versions through 5.6.1. It carries a CVSS 3.1 score of 9.8 and permits an unauthenticated remote attacker to issue requests that impersonate privileged users such as administrators.

An attacker can exploit the issue over the network without credentials or user interaction to obtain full administrative access on any site running the vulnerable plugin, resulting in complete control over the WordPress installation.

Public advisories and technical analyses published by the WooCommerce team and independent researchers detail the flaw and are available at the referenced URLs, including guidance on applying the corrective update.

The associated EPSS score stands at 0.9367 with no reported change from its peak value.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

An issue in WooCommerce Payments plugin for WordPress (versions 5.6.1 and lower) allows an unauthenticated attacker to send requests on behalf of an elevated user, like administrator. This allows a remote, unauthenticated attacker to gain admin access on a site…

more

that has the affected version of the plugin activated.

CWE(s)

Related Threats

CVEs Like This One

CVE-2023-45050Same product class: WordPress / CMS plugin
CVE-2024-10076Same product class: WordPress / CMS plugin
CVE-2023-47787Same product class: WordPress / CMS plugin
CVE-2023-27429Same product class: WordPress / CMS plugin
CVE-2024-4392Same product class: WordPress / CMS plugin
CVE-2023-2996Same product class: WordPress / CMS plugin
CVE-2024-1310Same product class: WordPress / CMS plugin
CVE-2023-47774Same product class: WordPress / CMS plugin
CVE-2024-10075Same product class: WordPress / CMS plugin
CVE-2024-10858Same product class: WordPress / CMS plugin

Affected Assets

automattic
woocommerce payments
4.8.0 — 4.8.2 · 5.0.0 — 5.0.4 · 5.1.0 — 5.1.3
automattic
woopayments
4.9.0, 5.3.0, 5.4.0 · 5.6.0 — 5.6.2

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-287

Detects unauthorized successful logons resulting from improper authentication implementations.

addresses: CWE-287

Documented procedures ensure personnel are trained on authentication mechanisms, tangibly lowering the risk of improper authentication being exploited.

addresses: CWE-287

Security awareness training instructs users on secure authentication practices and avoiding credential compromise.

addresses: CWE-287

Training on authentication mechanisms and best practices decreases the occurrence of improper authentication.

addresses: CWE-287

Non-repudiation requires strong authentication mechanisms to irrefutably attribute performed actions to specific individuals or processes.

addresses: CWE-287

Session content review can reveal authentication bypasses or failures in session establishment.

addresses: CWE-287

Review of authentication-related audit records can detect improper authentication mechanisms or bypasses.

addresses: CWE-287

Assessments check authentication mechanisms for correct implementation and effectiveness, reducing successful authentication bypass attempts.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

blocks

Mandating segregated approval and oversight for non-human identities reduces the chance that weak or orphaned credentials can be exploited for unauthorized authentication.

blocks

A.5.17 directly mandates generation of non-guessable unique secrets, secure transmission, immediate change of defaults/temporary creds, strong password enforcement, no-reuse, and compromise response, which stops most improper-authentication exploits at source; the bounded remainder is non-password authentication methods and sufficiency-of-proof cases (e.g. IA-2/IA-5 enhancements) left to other controls.

blocks

Security requirements specified early and verified through testing drive the consistent implementation of authentication mechanisms, decreasing the likelihood that authentication steps are omitted or incorrectly applied.

blocks

A.8.26 explicitly requires identifying and addressing authentication-related requirements (including level of trust in identity via 8.5 and 5.17) as part of application development or acquisition, which prevents a slice of CWE-287 but leaves the dominant sufficiency-of-proof aspects (IA-2/IA-5) and many implementation defects untouched.

blocks

A.8.27 mandates security-by-design principles (least privilege, default-deny, never-trust/always-verify, MFA, end-to-end encryption of requests, distrust-external-input, secure session control, and explicit authentication/authorization in every layer), which directly stops most improper-authentication flaws from being exploitable; the bounded remainder is insufficient-proof cases that live only in the strength or correctness of the credential itself (IA-5/IA-2 territory).

blocks

A.8.5 directly mandates appropriate-strength authentication techniques, MFA for critical systems, protected log-on procedures, brute-force resistance, no cleartext passwords/transmission, and session controls that stop exploitation of insufficient proof of identity; the bounded remainder is cases where the chosen technique itself is flawed or insufficiently implemented (e.g. weak biometrics without fallback).

Hardening callouts derived

DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.

  • No fine-grained STIG row for CWE-287, a class-level weakness. Rules are authored against its narrower children: CWE-295, CWE-306.

References