Answer in brief
CVE-2026-77339 records a Medium severity (CVSS 0.0) vulnerability in Process Compose: Browser DNS rebinding lets websites control local process-compose MCP tools. The current sources do not mark it as known exploited. The current feed maps F1bonacc1/process-compose (generic), github.com/f1bonacc1/process-compose (go), github.com/f1bonacc1/process-compose (go). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 0.0. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps F1bonacc1/process-compose (generic), github.com/f1bonacc1/process-compose (go), github.com/f1bonacc1/process-compose (go). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| F1bonacc1/process-composegeneric | < 1.120.0 | Not reported |
| github.com/f1bonacc1/process-composego | <1.120.0 | 1.120.0 |
| github.com/f1bonacc1/process-composego | >=0 <1.120.0 | 1.120.0 |
Published upstream
Sep 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 18, 2026
Process Compose is a scheduler and orchestrator for non-containerized applications. Prior to 1.120.0, the MCP SSE listener in src/mcp/server.go accepts browser-origin requests to /sse and the returned message endpoint without validating the Host header, validating the Origin header, or authenticating the caller. When MCP SSE is enabled, a malicious website can use DNS rebinding to reach the loopback listener and issue MCP requests. If expose_control_tools is enabled, the attacker can enumerate process state, read or search logs, truncate logs, and start, stop, restart, or scale local processes; configured user-defined tools can expose additional commands and output. The Gin REST API token middleware does not protect this separately started MCP listener. This issue is fixed in version 1.120.0.
Quoted source text, attributed separately from HOL analysis.