ZeroHour

CVE-2026-19295

large

Authenticated OS command injection in IBM Langflow OSS

CVSS 3.1
9.9 critical
EPSS
<1%p59
Published
()
Modified
AI analysis

IBM Langflow OSS 1.0.0 through 1.11.1 contains a command/code injection flaw (CWE-95) in which a user-supplied 'type' field value in a saved flow is not neutralized when it is used during a flow build. An authenticated user can save a flow with a crafted type field value and then trigger a build of a wrapper flow that references it, causing the server process to execute attacker-controlled operating system commands. This escalates privileges from a restricted 'authenticated flow user' to arbitrary OS-level command execution running under the Langflow server process identity, and it works even when administrators have disabled custom components via LANGFLOW_ALLOW_CUSTOM_COMPONENTS=false. Any deployment running the affected versions is exposed, with the greatest risk where untrusted users can create or edit flows or where the server is network-reachable. Exploitation has not been observed: there is no public proof of concept, the flaw is not in CISA's KEV catalog, and EPSS currently gives it a 1% probability of exploitation in the next 30 days.

What to do: Upgrade all Langflow OSS instances in the 1.0.0-1.11.1 range to the first patched release after 1.11.1, per IBM's advisory. Until patched, restrict who can save or create flows to trusted users and avoid exposing the server to the internet, and note that setting LANGFLOW_ALLOW_CUSTOM_COMPONENTS=false does not prevent this flaw. Audit saved flows for unexpected 'type' field values and review what privileges the Langflow service account holds on the host.

Affected
IBM Langflow OSS1.0.0 through 1.11.1 (inclusive)
Estimated exposure
largetens of thousands of deployments (roughly 1k-10k directly internet-exposed) — Estimate based on Langflow's position as one of the most widely adopted open-source LLM workflow builders (tens of thousands of GitHub stars and millions of cumulative Docker pulls), typically self-hosted by AI development teams inside…

Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.

Description

IBM Langflow OSS 1.0.0 through 1.11.1 allows an authenticated attacker to execute arbitrary operating system commands in the server process by saving a flow with a crafted type field value and triggering a build of a wrapper flow that references it. This allowed privilege escalation from "authenticated flow user" to arbitrary OS-level command execution under the server process identity, bypassing the LANGFLOW_ALLOW_CUSTOM_COMPONENTS=false policy control.

Vendors
langflow
Products
langflow
Weakness
CWE-95
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

In the news

Metasploit Wrap Up: This One Goes to Sixteen!

Metasploit adds 16 modules including 10 exploits, five covering CISA KEV vulnerabilities in Cisco, SonicWall, PaperCut, JetBrains and Langflow.

Rapid7's weekly Metasploit update ships 16 new modules, 10 of them exploit modules, with five targeting CISA KEV entries. New exploits cover Cisco Secure Firewall Management Center auth bypass (CVE-2026-20079), a SonicWall SMA1000 SSRF-to-root RCE chain (CVE-2026-83548/CVE-2026-83549), JetBrains TeamCity deserialization RCE (CVE-2026-63077), PaperCut NG/MF chain (CVE-2026-81578/CVE-2026-82078), and Langflow authenticated RCE (CVE-2026-19295). The SonicWall and PaperCut chains were reported as actively exploited zero-days, and a new ESC8 relay module exploits CVE-2026-20929 against AD CS Web Enrollment.

Rapid7 Blog · 4d agoTools in the wildCVE-2025-66516CVE-2025-54988CVE-2026-20929+8 CVEs1