Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2021-34646 is a critical-severity Authentication Bypass by Spoofing (CWE-290) vulnerability in Booster Booster For Woocommerce. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Adversary-in-the-Middle (T1557); ranked in the top 1% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-21296
Vulnerability Data
Versions up to, and including, 5.4.3, of the Booster for WooCommerce WordPress plugin are vulnerable to authentication bypass via the process_email_verification function due to a random token generation weakness in the reset_and_mail_activation_link function found in the ~/includes/class-wcj-emails-verification.php file. This allows…
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attackers to impersonate users and trigger an email address verification for arbitrary accounts, including administrative accounts, and automatically be logged in as that user, including any site administrators. This requires the Email Verification module to be active in the plugin and the Login User After Successful Verification setting to be enabled, which it is by default.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 11 hardening rules · 5 OS baselines
V6.4.3V10.4.16V10.5.1V11.4.3
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.
Reveals spoofed logon attempts through unexpected previous logon timestamps upon legitimate login.
Training specifically addresses recognizing spoofed communications and phishing that enable authentication bypass.
Requiring verifiable identity evidence at appropriate assurance levels makes it substantially harder for attackers to successfully spoof or impersonate users to obtain accounts.
Unique device authentication makes successful spoofing of device identity substantially more difficult to achieve.
Unique identification of non-organizational users reduces the feasibility of authentication bypass by spoofing.
Unique identification and authentication of services before communications makes spoofing of service identities substantially harder.
Isolated trusted path ensures the user interacts only with genuine system components, preventing spoofing of authentication interfaces or prompts.
Key generation under controlled management uses approved random-bit sources rather than insufficiently random values.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Protecting, conveying, and verifying identity assertions specifically prevents the spoofing that enables authentication bypass.
Requiring authentication of users/services/hardware directly counters spoofing-based bypass when strong methods are used.
Secure SDLC practices directly enforce use of cryptographically strong RNGs and catch insufficient randomness during design, coding, and testing.
Proofing and binding identities reduces spoofing opportunities during enrollment but does not address runtime authentication implementation flaws.
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.
Secure authentication control directly mitigates authentication bypass by spoofing.
Authentication information management directly addresses credential handling that prevents spoofing.
Cryptographic controls require use of approved, sufficiently random values for keys and nonces.
Security testing can detect spoofing vulnerabilities but does not prevent them by itself.
Access control policy reduces spoofing opportunities but does not prescribe authentication mechanisms.
Identity management supports unique identities but does not guarantee resistance to spoofing.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (4 rules)
- V-248563 The OL 8 SSH server must be configured to use strong entropy. prevents CWE-330
- V-248599 OL 8 must enable the hardware random number generator entropy gatherer service. prevents CWE-330
- V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-290
Oracle Linux 9 (1 rule)
- V-271511 OL 9 must enable the hardware random number generator entropy gatherer service. prevents CWE-330
RHEL 7 (1 rule)
- V-204442 The Red Hat Enterprise Linux operating system must not have the rsh-server package installed. prevents CWE-290
RHEL 8 (4 rules)
- V-230492 RHEL 8 must not have the rsh-server package installed. prevents CWE-290
- V-244527 RHEL 8 must have the packages required to use the hardware random number generator entropy gatherer service. prevents CWE-330
- V-230253 RHEL 8 must ensure the SSH server uses strong entropy. prevents CWE-330
RHEL 9 (1 rule)
- V-257782 RHEL 9 must enable the hardware random number generator entropy gatherer service. prevents CWE-330