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+---
+title: Security Changelog
+description: Security advisories for Molecule AI platform fixes.
+---
+
+# Security Changelog
+
+This page documents security fixes shipped in the Molecule AI platform. Each entry describes the vulnerability, its severity, the affected code, and the remediation.
+
+---
+
+## 2026-04-20 — CWE-22: Path Traversal in `copyFilesToContainer`
+
+**Severity:** High (CWE-22)
+**PRs:** [#1271](https://github.com/Molecule-AI/molecule-core/pull/1271), [#1270](https://github.com/Molecule-AI/molecule-core/pull/1270), [#1267](https://github.com/Molecule-AI/molecule-core/pull/1267)
+**Affected:** `workspace-server/internal/handlers/container_files.go` — `TemplatesHandler.copyFilesToContainer`
+
+### Vulnerability
+
+`copyFilesToContainer` accepted raw map keys as tar header names without validation. A malicious caller could embed `../` sequences in a filename key to write files outside the intended volume mount, potentially overwriting system files or configuration outside the workspace's allocated storage.
+
+### Fix
+
+Two-layer defense:
+
+1. **Handler-level guard** (`validateRelPath` in `templates.go`): `filepath.Clean` + `filepath.IsAbs` + `strings.Contains("..")` check blocks traversal at HTTP entry point before any container interaction.
+2. **Archive boundary guard** (in `copyFilesToContainer`): Validates each filename with `filepath.Clean` + `filepath.IsAbs` + `strings.HasPrefix(clean, "..")` before writing the tar header. The validated `archiveName` is constructed as `filepath.Join(destPath, name)`, guaranteeing the header path is always inside the `/configs` volume mount.
+
+Both layers must remain in sync — removing either layer re-opens the vulnerability.
+
+### User-facing summary
+
+File writes to workspace containers now validate all paths before writing to the tar archive. Attempts to write outside the allocated workspace volume are rejected with `400 Bad Request`.
+
+---
+
+## 2026-04-20 — CWE-78: Shell Injection in `deleteViaEphemeral`
+
+**Severity:** High (CWE-78)
+**PR:** [#1310](https://github.com/Molecule-AI/molecule-core/pull/1310)
+**Affected:** `workspace-server/internal/handlers/container_files.go` — `TemplatesHandler.deleteViaEphemeral`
+
+### Vulnerability
+
+`deleteViaEphemeral` interpolated `filePath` directly into a shell command string using bash's string-concatenation syntax:
+
+```go
+cmd := exec.Command("sh", "-c", "rm -rf /configs/"+filePath) // UNSAFE — path becomes shell code
+```
+
+A path containing shell metacharacters (e.g., `foo; cat /etc/passwd`) could execute arbitrary commands in the ephemeral Alpine container, potentially escaping the intended delete operation.
+
+### Fix
+
+Replaced the shell-form `exec.Command` with the **exec-form argument array** so the path is passed as a plain argument, never interpreted as shell code:
+
+```go
+cmd := exec.Command("rm", "-rf", "/configs", filePath) // SAFE — path is argument only
+```
+
+The `validateRelPath` handler-level guard (`filepath.Clean` + `filepath.IsAbs` + `strings.Contains("..")`) is preserved as an additional layer.
+
+### User-facing summary
+
+Workspace file deletion operations now use safe argument-passing and validate all paths before execution. Shell metacharacters in delete paths are treated as literal filenames and never interpreted as commands.
+
+---
+
+## 2026-04-21 — CWE-918: SSRF in MCP / A2A Proxy Endpoints
+
+**Severity:** High (CWE-918)
+**PRs:** [#1274](https://github.com/Molecule-AI/molecule-core/pull/1274), [#1302](https://github.com/Molecule-AI/molecule-core/pull/1302)
+**Affected:** `workspace-server/internal/handlers/mcp.go` — `isSafeURL`, `isPrivateOrMetadataIP`; `workspace-server/internal/handlers/a2a_proxy.go`
+
+### Vulnerability
+
+Workspace URL resolution and outbound HTTP calls in the MCP and A2A proxy handlers did not validate that the target address was reachable from the platform. Without validation, a malicious workspace configuration could redirect platform requests to internal infrastructure (cloud metadata services, RFC-1918 databases, link-local monitoring endpoints) or loopback interfaces.
+
+### Fix
+
+`isSafeURL` validates every outbound URL before making an HTTP request:
+
+- **Scheme enforcement:** Only `http` and `https` are allowed.
+- **Direct IP checks:** Loopback (`127.0.0.0/8`), unspecified (`0.0.0.0`), and link-local (`fe80::/10`) addresses are blocked.
+- **Private IP range blocking** via `isPrivateOrMetadataIP`:
+  - RFC-1918 private: `10.0.0.0/8`, `172.16.0.0/12`, `192.168.0.0/16`
+  - CGNAT shared address space: `100.64.0.0/10`
+  - Cloud metadata services: `169.254.0.0/16`
+  - Documentation and test ranges: `192.0.2.0/24`, `198.51.100.0/24`, `203.0.113.0/24`
+- **DNS rebinding defense:** Hostnames are resolved, and each resolved IP is checked against the blocklist. DNS resolution failures block the request entirely.
+
+URLs that fail validation return a descriptive error; requests are never sent to unsafe destinations.
+
+### User-facing summary
+
+Platform outbound requests from workspaces (MCP tool calls, A2A proxy routing) now validate all target URLs against a comprehensive blocklist before sending. Requests to private IP ranges, cloud metadata endpoints, and loopback addresses are rejected.
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