JunoClaw: MCP write tools exposed raw BIP-39 mnemonic as a tool-call parameter

published 2026-05-12 5 mo ago modified 2026-10-26 13 d ago also EUVD-2026-29541

cvss: 9.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 13%
public exploits: 0; none known

JunoClaw is an agentic AI platform built on Juno Network. Prior to 0.x.y-security-1, every MCP write tool (send_tokens, execute_contract, instantiate_contract, upload_wasm, ibc_transfer, etc.) accepted 'mnemonic: string' as an explicit tool-call parameter. The BIP-39 seed was consequently embedded in the LLM tool-call JSON, exposing it to any transport, log, or telemetry surface in the path between the LLM provider and the MCP process. This vulnerability is fixed in 0.x.y-security-1.

Patch / fix

links 2

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: total
Assessed: 5 mo ago (2026-05-13)

Exploit prediction

0.22% chance of exploitation in the next 30 days, higher than 13% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Dragonmonk111 junoclaw

Classification

Weakness

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
CWE-312 Cleartext Storage of Sensitive Information
CWE-522 Insufficiently Protected Credentials
CWE-532 Insertion of Sensitive Information into Log File

References

Sources

CVE List CVE-2026-43992
NVD CVE-2026-43992

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary