Cyber Resilience

CVE-2023-26154

Pubnub ≤ 0.4.0

Public PoC
Published
06 December 2023
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 5.9
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0095 59th percentile
Risk Priority 48 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-2023-26154 is a medium-severity Insufficient Entropy (CWE-331) vulnerability in Pubnub Pubnub. Its CVSS base score is 5.9 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Brute Force (T1110); ranked in the top 41% 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

Vulnerability Data

Versions of the package pubnub before 7.4.0; all versions of the package com.pubnub:pubnub; versions of the package pubnub before 6.19.0; all versions of the package github.com/pubnub/go; versions of the package github.com/pubnub/go/v7 before 7.2.0; versions of the package pubnub before 7.3.0;…

more

versions of the package pubnub/pubnub before 6.1.0; versions of the package pubnub before 5.3.0; versions of the package pubnub before 0.4.0; versions of the package pubnub/c-core before 4.5.0; versions of the package com.pubnub:pubnub-kotlin before 7.7.0; versions of the package pubnub/swift before 6.2.0; versions of the package pubnub before 5.2.0; versions of the package pubnub before 4.3.0 are vulnerable to Insufficient Entropy via the getKey function, due to inefficient implementation of the AES-256-CBC cryptographic algorithm. The provided encrypt function is less secure when hex encoding and trimming are applied, leaving half of the bits in the key always the same for every encoded message or file. **Note:** In order to exploit this vulnerability, the attacker needs to invest resources in preparing the attack and brute-force the encryption.

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.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-13399Shared CWE-331
CVE-2025-29311Shared CWE-331
CVE-2023-38357Shared CWE-331
CVE-2023-34973Shared CWE-331
CVE-2026-46473Shared CWE-331
CVE-2026-4827Shared CWE-331
CVE-2024-9055Shared CWE-331
CVE-2026-34236Shared CWE-331
CVE-2024-3411Shared CWE-331
CVE-2024-38270Shared CWE-331

Affected Assets

pubnub
c-core
≤ 4.5.0
pubnub
kotlin
≤ 7.7.0
pubnub
pubnub
≤ 0.4.0 · ≤ 7.2.0 · 3.6.4 — 4.3.0
pubnub
swift
≤ 6.2.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 6 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.5.2
  • V11.3.4

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-331

Approved key-establishment methods mandate sufficient entropy during key generation, eliminating entropy-starved keys.

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 explicitly include vetted RNG and entropy sources, directly preventing this weakness while covering many other development concerns.

PR.AA-03 partial match
prevents

Password-strength policies implicitly require sufficient entropy, but the control addresses authentication rather than algorithmic randomness.

PR.DS-01 partial match
prevents

Proper encryption for data-at-rest requires sufficient entropy for keys/nonces; eliminating the weakness therefore supports but does not fully realize the control.

PR.DS-02 partial match
prevents

Cryptographic protection of data-in-transit depends on adequate entropy; the weakness directly undermines the control's effectiveness.

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

Mandates use of cryptography that must rely on sufficient entropy sources.

finds

Security testing can detect insufficient-entropy defects before release.

prevents

Secure-SDLC activities include entropy validation during design and testing.

prevents

Secure-coding rules can explicitly forbid weak random-number generation.

degrades

Requires secure authentication mechanisms that depend on unpredictable secrets.

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 (2 rules)
  • V-248524 OL 8 must implement NIST FIPS-validated cryptography for the following: To provision digital signatures, to generate cryptographic hashes, and to protect data requiring data-at-rest protections in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards. prevents CWE-331
  • V-248563 The OL 8 SSH server must be configured to use strong entropy. prevents CWE-331
RHEL 7 (1 rule)
  • V-204497 The Red Hat Enterprise Linux operating system must implement NIST FIPS-validated cryptography for the following: to provision digital signatures, to generate cryptographic hashes, and to protect data requiring data-at-rest protections in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards. prevents CWE-331
RHEL 8 (1 rule)
  • V-230223 RHEL 8 must implement NIST FIPS-validated cryptography for the following: To provision digital signatures, to generate cryptographic hashes, and to protect data requiring data-at-rest protections in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards. prevents CWE-331

References