CISA adds Langflow and Trend Micro Apex One to KEV

CVE-2025-34291 — Langflow Origin Validation Error (RCE)

CVSS: 9.4
CWE: CWE-346 — Origin Validation Error
Affected Versions: Langflow ≤ 1.6.9

Vulnerability Summary

Researchers at Obsidian Security uncovered a critical vulnerability chain in Langflow, enabling complete account takeover and Remote Code Execution simply by having a user visit a malicious webpage.

Root Cause — Three-Weakness Chain

CVE-2025-34291 exploits three combined weaknesses: overly permissive CORS, lack of CSRF protection, and an endpoint that allows code execution by design.

Specifically:

• An allow_origins='*' with allow_credentials=True CORS configuration combined with a refresh token cookie set as SameSite=None allows a malicious webpage to perform cross-origin requests that include credentials and successfully call the refresh endpoint — allowing an attacker-controlled origin to obtain fresh access and refresh token pairs for a victim session.

Impact

Successful exploitation not only compromises the Langflow instance but also exposes all sensitive access tokens and API keys stored within the workspace, triggering a cascading compromise across all integrated downstream services in cloud and SaaS environments.

Threat Actor Attribution

The vulnerability has been exploited by Iranian state-sponsored hacking group MuddyWater to obtain initial access to target networks, per a Ctrl-Alt-Intel analysis published in March 2026. Additionally, threat actors deployed the Flodric botnet through compromised Langflow instances.

Exploitation Timeline

Active exploitation of CVE-2025-34291 was observed starting January 23, 2026.

CVE-2026-34926 — Trend Micro Apex One Directory Traversal

CVSS: 6.7
Product: Trend Micro Apex One (On-Premise)
CWE: Directory Traversal

Vulnerability Summary

Trend Micro Apex One (on-premise) contains a directory traversal vulnerability that could allow a pre-authenticated local attacker to modify a key table on the server to inject malicious code to deploy to agents on affected installations.

Exploitation Confirmation

Trend Micro confirmed it observed at least one instance of an attempt to actively exploit this vulnerability in the wild.

Why This Is High-Risk Despite 6.7 CVSS

The second KEV addition targets Trend Micro Apex One on-premise, a widely deployed EDR solution common in government, defense, and critical infrastructure sectors. Exploiting a vulnerability in such a product is a nightmare scenario — an attacker can leverage it as a launchpad across the managed environment. The pre-auth constraint is local, but insider threat, VPN-connected users, or existing footholds all create viable attack paths.

FCEB Remediation Deadline

Federal agencies must remediate by June 4, 2026, under Binding Operational Directive 22-01.

Remediation

Langflow:

• Upgrade beyond 1.6.9 immediately
• Set explicit LANGFLOW_CORS_ORIGINS environment variable to restrict allowed origins — do not leave wildcard
• Enforce SameSite=Strict or SameSite=Lax on all cookies
• Audit all stored API keys and tokens in compromised or unpatched instances; rotate them

Trend Micro Apex One:

• Apply vendor-issued patches per the Trend Micro advisory
• Restrict local access to the Apex One server management interface
• Monitor agent deployment logs for anomalous code injection patterns
• Review recently deployed agent configurations for unauthorized modifications