7,000 Langflow servers are under attack. LangGraph and LangChain have the same holes

Your AI agent did exactly what it was designed to do. The framework underneath it just handed an attacker a shell on the box that holds your OpenAI key, your database credentials, and your CRM tokens.

That is not a hypothetical. In a few months, three of the most widely deployed AI agent frameworks each turned a known, ordinary bug class into a way through. Check Point Research chained a SQL injection in LangGraph’s SQLite checkpointer to full remote code execution. Tenable and VulnCheck tracked a path traversal in Langflow’s file upload endpoint to active, in-the-wild RCE. Cyera documented a path traversal in LangChain-core’s prompt loader that reads your secrets off disk. Two paths to a shell, one to your keys. They are the same bug, wearing three frameworks.

These frameworks became production infrastructure faster than anyone secured them. They store agent state, take file uploads, load prompt configs, and hold the credentials to databases, CRMs, and internal APIs. The edge tools watch traffic. The endpoint tools watch processes. Neither was built to treat an imported framework as a boundary worth guarding, and that blind spot is exactly where all three chains live, widening every week as these frameworks ship to production.

The LangGraph chain, SQL injection to a Python shell

Start with the one most teams pulled into production this quarter. LangGraph gives AI agents memory through checkpointers, the persistence layer that stores execution state. It has cleared over 50 million downloads a month. Yarden Porat of Check Point Research took that layer apart and found three vulnerabilities. Two of them chain to RCE.

CVE-2025-67644, rated CVSS 7.3, is a SQL injection in the SQLite checkpointer. The function that builds the WHERE clause for checkpoint lookups drops user-controlled filter keys straight into the query with no parameterization and no escaping. This does not hit everyone, but where it hits, it is serious. A deployment is exposed when it self-hosts LangGraph on the SQLite or Redis checkpointer and lets untrusted input reach get_state_history() or a similar history endpoint. Meet those conditions, and an attacker who controls the filter writes a fabricated row straight into the checkpoint table. Run LangChain’s managed LangSmith platform on PostgreSQL, and the exposure is gone.

Then CVE-2026-28277, CVSS 6.8, finishes the job. LangGraph’s msgpack checkpoint decoder rebuilds Python objects from the stored data, which lets it import a module and call a named function with attacker-supplied arguments. That step needs write access to the checkpoint store; the SQL injection is what grants it remotely. LangGraph loads the forged row as a legitimate checkpoint, the decoder runs the specified function, including os.system, and code executes under the identity of the agent server. A third issue, CVE-2026-27022, CVSS 6.5, reaches the same place through the Redis checkpointer.

There has been no confirmed exploitation in the wild yet. A working proof-of-concept is public in Check Point’s disclosure. The fixes are version bumps: langgraph-checkpoint-sqlite to 3.0.1, langgraph to 1.0.10, and langgraph-checkpoint-redis to 1.0.2.

The Langflow chain, one unauthenticated request to RCE

Langflow is the one already under attack. CVE-2026-5027, CVSS 8.8, is a path traversal in the POST /api/v2/files endpoint, which takes the filename straight from the form data and writes it to disk unsanitized. An attacker packs that filename with traversal sequences and drops a file anywhere, such as a cron job in /etc/cron.d/. Because Langflow ships with auto-login enabled in its default configuration, an exposed instance needs no credentials at all. A single unauthenticated request reaches the endpoint, and the next cron run hands over a shell.

VulnCheck’s Caitlin Condon confirmed exploitation on June 9: “Our Canaries observed exploitation of CVE-2026-5027 that successfully leveraged the path traversal to write what appear to be test files on victim systems.” Censys put roughly 7,000 exposed instances on the internet, most in North America. This is the third Langflow flaw to draw active exploitation this year, after CVE-2025-34291, which the Iranian state-sponsored group MuddyWater weaponized and which CISA added to its Known Exploited Vulnerabilities catalog in May. CVE-2026-5027 itself was patched in version 1.9.0, released April 15.

The timeline is what sets the clock. The patch shipped April 15. Attacks started in June, and VulnCheck added CVE-2026-5027 to its exploited-vulnerabilities list June 8 once its sensors caught the first in-the-wild hits. Every instance left unpatched between those two dates has been sitting in the open for almost two months. The lesson for security teams is to start the patch clock at disclosure, not at a federal catalog entry.

The LangChain-core gap, arbitrary file reads through the prompt loader

LangChain-core, the foundation under both, disclosed CVE-2026-34070, CVSS 7.5, a path traversal in its legacy prompt-loading API. The load_prompt() functions read a file path out of a config dict with no check against traversal sequences or absolute paths, so an attacker who influences that path reads arbitrary files the process can reach, including the .env file holding OPENAI_API_KEY and ANTHROPIC_API_KEY. Cyera paired it with CVE-2025-68664, CVSS 9.3, a deserialization flaw that resolves environment secrets through a crafted object. The fix versions differ, which matters when you patch: CVE-2026-34070 lands in langchain-core 1.2.22 and 0.3.86; CVE-2025-68664 lands earlier in 1.2.5 and 0.3.81. Clear both, or the higher-severity flaw stays live behind a patched one.

Three frameworks, three classic AppSec bugs. Path traversal. SQL injection. Unsafe deserialization. Nothing exotic, nothing AI-specific, just old vulnerabilities living inside new infrastructure. None of this is a frontier-model problem. It is plumbing, sitting in the layer where AI meets the enterprise.

Why the scanner cannot see it

Merritt Baer, CSO at Enkrypt AI and former deputy CISO at AWS, has named what makes this kind of failure hard to see coming. It does not announce itself as an AI problem. "CISOs will experience MCP insecurity not in the abstract, but when an employee pastes sensitive data into a tool, or when an attacker finds an unauthenticated MCP server in your cloud," Baer told VentureBeat. "It won't feel like 'AI risk.' It will feel like your traditional security program failing." The framework chains here are the same shape. An exposed Langflow instance is an unauthenticated server in your cloud, and the alert, if one fires, reads like an ordinary incident.

That is the gap in one sentence. The exploit lives in the framework your code imports. The WAF never sees a msgpack decoder running three layers down. The EDR watches the agent server make the same process calls it makes a thousand times a day and waves it through. Both tools are doing their job. Nobody scoped the framework itself as the thing that could turn on you.

The root cause is older than AI, and Baer names it. “MCP is shipping with the same mistake we’ve seen in every major protocol rollout: insecure defaults,” she told VentureBeat. “If we don’t build authentication and least privilege in from day one, we’ll be cleaning up breaches for the next decade.” Langflow’s auto-login is that mistake shipped. LangChain-core’s unguarded prompt loader is that mistake shipped. The convenient default is the vulnerability. And the moment an agent connects to anything, that risk compounds. “You’re not just trusting your own security, you’re inheriting the hygiene of every tool, every credential, every developer in that chain,” Baer said. “That’s a supply chain risk in real time.”

There is a governance failure layered on top of the technical one, and it is the same miscategorization Assaf Keren, chief security officer at Qualtrics and former CISO at PayPal, has flagged in adjacent tooling.