CVE-2026-104317

Langflow message-broker deserialization can execute code

IBM / Langflow · Langflow OSS

First documented disclosure · Review checkpoint

Summary

Code execution in the vulnerable process context.

Severity and exploitation evidence

High · 8.1/10 · CVSS 3.1. Severity source.

Exploitation not established: The reviewed primary records do not establish malicious exploitation or a confirmed victim.

Exploitation evidence source

Technical severity is not a measure of observed attacks or of risk to your deployment. Attempts, demonstrations, and successful compromise retain the qualifications in the source.

How the weakness works

Untrusted data reaching the message broker is deserialized unsafely. The precise serializer and payload are not disclosed.

Conditions required

Reachability to the affected message broker; IBM’s vector requires no prior application privileges but marks high complexity.

Potential impact

Code execution in the vulnerable process context.

Affected versions and configurations

IBM lists Langflow OSS 1.0.0 through 1.12.3.

Fix and mitigation status

1.12.4 per IBM; this is an issue-specific fix, not assurance that the old release addresses later findings.

Practical next steps

Upgrade to a current supported release containing the fix; back up the deployment and validate workflow behavior.

Operating lesson

Keep brokers private and reject untrusted executable serialization formats.

Evidence and limits

IBM bulletin 7293015 was initially published 2026-10-19; the CNA record followed on 2026-10-29. Earlier upstream patches are not assigned to this CVE by inference. Exact technical details absent from the public record remain unknown; a CVSS score is not an observed incident.

Sources