CVE-2026-53604
nebula-mesh is a self-hosted control plane for Slack Nebula mesh VPN. Prior to version 0.3.8, the web handler renderMobileBundle passes the real *pki.CAResolver directly into mobilebundle.Build. Inside Build, resolver.LoadByID decrypts the CA's ed25519 private key into a *pki.CAManager, but Build never calls CAManager.Wipe() on any return path. As a result, when a mobile-bundle request goes through the web UI and Build returns — especially on error (missing network, invalid prefix, DB error, signing failure) — the plaintext CA private key remains on the Go heap, unwiped, until garbage collection. An attacker able to read process memory (core dump, swap, memory-scraping) can recover the CA signing key, which would allow minting arbitrary host certificates for the mesh. The API handler already does this correctly: it loads the CAManager, defer caMgr.Wipe(), and wraps it in caManagerResolver. Only the web path is affected. This issue has been patched in version 0.3.8.
What this means for your business
- FIRST's prediction model gives it a 0.1% chance of attack attempts being seen in the next 30 days, ranking above 1% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- Not yet scored
- CVSS v4
- 7.1
- Weakness
- CWE-212
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-04
- Last modified
- 2026-09-08
- Sources
- NVD