SSRF (Server-Side Request Forgery) in mcp-run-python (CVE-2026-25904)
Summary
SSRF in mcp-run-python (CVE-2026-25904). Risk of unauthorized operations or information disclosure. Exploitable via localhost.
Original description
The description as published by the source.
Impact
Server-Side Request Forgery (SSRF):
A security vulnerability exists in the mcp-run-python tool (specifically within the Pydantic-AI integration) due to an overly permissive Deno sandbox configuration.
The tool configures the Deno runtime—which is intended to isolate the execution of untrusted Python code—with network permissions that include access to the host's loopback interface (localhost). Consequently, malicious Python code executed through the tool can bypass network isolation and send HTTP requests to internal services running on the host machine. This allows attackers to interact with local APIs, databases, or cloud metadata services that should not be accessible from the sandbox.
Patches
No Patch Available:
The mcp-run-python project is currently archived and maintainers have indicated it is unlikely to receive a fix.
Recommendation:
Users are strongly advised to immediately stop using this package.
If functionality is required, users must migrate to an alternative execution environment that enforces strict network isolation (e.g., blocking all outbound traffic or explicitly denying access to 127.0.0.1/::1).
Workarounds
There are no configuration-based workarounds provided by the package itself. Remediation requires modifying the source code to restrict the Deno permissions (specifically removing or narrowing the --allow-net flag) or moving the execution to a container with no network access.
Resources
- [CV…
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-25904 has been found in mcp-run-python.
Attackers can target a specific entry point like localhost over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "mcp-run-python CVE-2026-25904" on the vendor's site.
CVE-2026-25904 (mcp-run-python) — CWE-918
Attack vector: remote (network-reachable) / unauthenticated
Attack surface: localhost
Workaround: There are no configuration-based workarounds provided by the package itself.
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
SSRF (CWE-918) exists in mcp-run-python. Attackers reach the vulnerable code path via localhost without authentication.
Check the vendor advisory for the affected versions of mcp-run-python. Attack surface: localhost.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Workaround: There are no configuration-based workarounds provided by the package itself.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'mcp-run-python' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'mcp-run-python' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
mcp-run-pythonを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply temporary workaround mitigate
There are no configuration-based workarounds provided by the package itself.パッチが適用されるまでの応急処置として、There are no configuration-based workarounds provided by the package itself. を実施。回避策の副作用 (機能低下) を確認した上で。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- web research.jfrog.com