CVE-2026-55102
CVE-2026-55102 is a security vulnerability in hashi-vault-js. O3 Security confirms whether CVE-2026-55102 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
hashi-vault-js: Vault token and secret values exposed in thrown errors
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
hashi-vault-jsnpmDescription
Summary
Vault token and secret values are exposed in thrown errors when using hashi-vault-js.
Details
Every API method in Vault.js executes throw parseAxiosError(err), which returns the raw AxiosError untouched. That error carries the full Axios configuration, including the X-Vault-Token header and the request body. Consuming applications that log caught errors (e.g., using console.error, pino, winston, Sentry, or APMs) inadvertently log the live Vault token in plaintext. Furthermore, write-path methods expose submitted passwords and secret values via err.config.data.
Impact
When consuming applications log intercepted exceptions, sensitive credentials such as tokens, passwords, and secrets are unknowingly exposed to application logs, monitoring services, and APM systems via the raw AxiosError. This may lead to authorization bypass or unauthorized access to the underlying Vault instance.
Patches
This vulnerability should be addressed by redacting err.config.headers['X-Vault-Token'] and err.config.data before re-throwing, or by throwing a purpose-built error containing only safe properties like status and message. Users should upgrade to a version that includes this fix.
Workarounds
If users cannot immediately update the library, they can mitigate this issue by capturing all exceptions thrown by hashi-vault-js and sanitizing or omitting the err.config object before passing the errors to logging utilities or crash reporters.
Acknowledgements
hashi-vault-js would like to thank Sebastián Alba Vives for reporting this vulnerability.
Resources
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | hashi-vault-js | all versions | 0.5.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for hashi-vault-js. 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 hashi-vault-js to 0.5.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-55102 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-2026-55102 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-2026-55102. 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-2026-55102 in your dependencies?
O3 detects CVE-2026-55102 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.