CVE-2023-26154
MEDIUMpubnub Insufficient Entropy vulnerability
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
pubnub🐹github.com/pubnub/go/v7🐹github.com/pubnub/go🐹github.com/pubnub/go/v6🐹github.com/pubnub/go/v5☕com.pubnub:pubnub-kotlin☕com.pubnub:pubnub📦pubnub+6 moreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io, Go packages — download data is not available via public APIs for these ecosystems.
Description
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; 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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | pubnub | all versions | 0.4.0 |
| 🐹Go | github.com/pubnub/go/v7 | all versions | 7.2.0 |
| 🐹Go | github.com/pubnub/go | all versions | 0.0.0-20231016150651-428517fef5b9 |
| 🐹Go | github.com/pubnub/go/v6 | all versions | 6.1.1-0.20231016150651-428517fef5b9 |
| 🐹Go | github.com/pubnub/go/v5 | all versions | 5.0.4-0.20231016150651-428517fef5b9 |
| ☕Maven | com.pubnub:pubnub-kotlin | all versions | 7.7.0 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pubnub. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update pubnub to 0.4.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-26154 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2023-26154 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2023-26154. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-26154 in your dependencies?
O3 detects CVE-2023-26154 across crates.io, Go, Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.