Cyber Resilience

CVE-2023-39979

Crypto Weakness in Moxa Mxsecurity ≤ 1.1.0

Published
02 September 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 0.0074 51th percentile
Risk Priority 72 floored blend · peak EPSS

Summary

CVE-2023-39979 is a critical-severity Small Space of Random Values (CWE-334) vulnerability in Moxa Mxsecurity. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Brute Force (T1110); ranked in the top 49% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

There is a vulnerability in MXsecurity versions prior to 1.0.1 that can be exploited to bypass authentication. A remote attacker might access the system if the web service authenticator has insufficient random values.  

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1110 Brute Force Credential Access
Adversaries may use brute force techniques to gain access to accounts when passwords are unknown or when password hashes are obtained.
T1110.001 Password Guessing Credential Access
Adversaries with no prior knowledge of legitimate credentials within the system or environment may guess passwords to attempt access to accounts.
T1110.002 Password Cracking Credential Access
Adversaries may use password cracking to attempt to recover usable credentials, such as plaintext passwords, when credential material such as password hashes are obtained.
T1606 Forge Web Credentials Credential Access
Adversaries may forge credential materials that can be used to gain access to web applications or Internet services.
T1606.001 Web Cookies Credential Access
Adversaries may forge web cookies that can be used to gain access to web applications or Internet services.
T1185 Browser Session Hijacking Collection
Adversaries may take advantage of security vulnerabilities and inherent functionality in browser software to change content, modify user-behaviors, and intercept information as part of various browser session hijacking techniques.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-39981Same product: Moxa Mxsecurity
CVE-2024-4740Same product: Moxa Mxsecurity
CVE-2023-33235Same product: Moxa Mxsecurity
CVE-2023-39982Same product: Moxa Mxsecurity
CVE-2024-4739Same product: Moxa Mxsecurity
CVE-2023-39983Same product: Moxa Mxsecurity
CVE-2023-39980Same product: Moxa Mxsecurity
CVE-2023-33236Same product: Moxa Mxsecurity
CVE-2023-5962Same vendor: Moxa
CVE-2023-3336Same vendor: Moxa

Affected Assets

moxa
mxsecurity
≤ 1.1.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 8 hardening rules · 4 OS baselines
Validate
Prove the fix (OWASP ASVS)

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-330

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.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require cryptographically strong RNGs with adequate value space, while fixing only this CWE addresses one narrow aspect of the control.

PR.AA-03 partial match
prevents

Authentication mechanisms often depend on random values (nonces, tokens), so the control can reduce exposure but eliminating the CWE does not achieve authentication outcomes.

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.

prevents

Cryptographic controls require adequate key/seed entropy, directly mitigating small random-value spaces.

finds

Security testing can detect insufficient randomness in tokens, session IDs, or keys.

prevents

Secure SDLC processes include verification steps that can catch insufficient randomness but do not directly specify RNG requirements.

prevents

Secure-coding standards explicitly call for cryptographically strong random number generation.

mitigates

Secure authentication mechanisms often rely on unpredictable tokens or nonces, so weak randomness undermines them.

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 (3 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-248600 OL 8 must have the packages required to use the hardware random number generator entropy gatherer service. prevents CWE-330
Oracle Linux 9 (1 rule)
  • V-271511 OL 9 must enable the hardware random number generator entropy gatherer service. prevents CWE-330
RHEL 8 (3 rules)
  • 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
  • V-230285 RHEL 8 must enable the hardware random number generator entropy gatherer service. prevents CWE-330
RHEL 9 (1 rule)
  • V-257782 RHEL 9 must enable the hardware random number generator entropy gatherer service. prevents CWE-330

References