Critical severity · published Mar 20, 2026
CVE-2026-33017
Langflow has Unauthenticated Remote Code Execution via Public Flow Build Endpoint
In wildKEV
9.8
CVSS
96.2%
EPSS
Yes
On KEV
Description
Langflow is a tool for building and deploying AI-powered agents and workflows. In versions prior to 1.9.0, the POST /api/v1/build_public_tmp/{flow_id}/flow endpoint allows building public flows without requiring authentication. When the optional data parameter is supplied, the endpoint uses attacker-controlled flow data (containing arbitrary Python code in node definitions) instead of the stored flow data from the database. This code is passed to exec() with zero sandboxing, resulting in unauthenticated remote code execution. This is distinct from CVE-2025-3248, which fixed /api/v1/validate/code by adding authentication. The build_public_tmp endpoint is designed to be unauthenticated (for public flows) but incorrectly accepts attacker-supplied flow data containing arbitrary executable code. This issue has been fixed in version 1.9.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)96.2% · higher than 100% of CVEs
Exploited in the wildYes
CISA KEVListed Mar 25, 2026
Federal remediation dueApr 8, 2026
Ransomware campaign useNot known
Affected products
Which versions
LA
langflow · langflow-ai
< 1.9.0 · source: vendor, NVD, KEV
In the news
VulnerabilityCritical
CISA sounds alarm on Langflow RCE, Trivy supply chain compromise after rapid exploitation
The US Cybersecurity and Infrastructure Security Agency (CISA) has added two new vulnerabilities to its Known Exploited Vulnerabilities catalog: CVE-2026-33017, a recently disclosed code injection vulnerability in Langflow, an open-source framework for building AI agents and workflows, and CVE-2026-33634, an embedded malicious code vulnerability in Aqua Security&#8217;s Trivy security scanner. Their addition to the catalog means that US federal civilian agencies are required to address the flaws within their networks by April 8 and 9, &#8230; More &#8594; The post CISA sounds alarm on Langflow RCE, Trivy supply chain compromise after rapid exploitation appeared first on Help Net Security .
Mar 27, 2026·Help Net Security
VulnerabilityCritical
U.S. CISA adds a Langflow flaw to its Known Exploited Vulnerabilities catalog
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) adds a flaw in Langflow to its Known Exploited Vulnerabilities catalog. The U.S. Cybersecurity and Infrastructure Security Agency (CISA) added a Langflow flaw, tracked as CVE-2026-33017 (CVSS score of 9.3), to its Known Exploited Vulnerabilities (KEV) catalog. Langflow is a popular tool used for building agentic AI workflows.  CVE-2026-33017 is a [&#8230;]
Mar 26, 2026·Security Affairs
VulnerabilityCritical
CISA: New Langflow flaw actively exploited to hijack AI workflows
The Cybersecurity and Infrastructure Security Agency (CISA) is warning that hackers are actively exploiting a critical vulnerability identified as CVE-2026-33017, which affects the Langflow framework for building AI agents. [...]
Mar 26, 2026·BleepingComputer
VulnerabilityHigh
CISA Adds One Known Exploited Vulnerability to Catalog
CISA has added one new vulnerability to its Known Exploited Vulnerabilities (KEV) Catalog , based on evidence of active exploitation. CVE-2026-33017 Langflow Code Injection Vulnerability This type of vulnerability is a frequent attack vector for malicious cyber actors and poses significant risks to the federal enterprise. Binding Operational Directive (BOD) 22-01: Reducing the Significant Risk of Known Exploited Vulnerabilities established the KEV Catalog as a living list of known Common Vulnerabilities and Exposures (CVEs) that carry significant risk to the federal enterprise. BOD 22-01 requires Federal Civilian Executive Branch (FCEB) agencies to remediate identified vulnerabilities by the due date to protect FCEB networks against active threats. See the BOD 22-01 Fact Sheet for more information. Although BOD 22-01 only applies to FCEB agencies, CISA strongly urges all organizations to reduce their exposure to cyberattacks by prioritizing timely remediation of KEV Catalog vulnerabilities as part of their vulnerability management practice. CISA will continue to add vulnerabilities to the catalog that meet the specified criteria .&nbsp;
Mar 25, 2026·CISA Advisories
VulnerabilityHigh
[CISA KEV] CVE-2026-33017: Langflow Langflow - Langflow Code Injection Vulnerability
Langflow contains a code injection vulnerability that could allow building public flows without requiring authentication.
LALangflowCVE-2026-33017
Mar 25, 2026·CISA KEV
VulnerabilityCritical
Critical Langflow Flaw CVE-2026-33017 Triggers Attacks within 20 Hours of Disclosure
A critical security flaw impacting Langflow has come under active exploitation within 20 hours of public disclosure, highlighting the speed at which threat actors weaponize newly published vulnerabilities. The security defect, tracked as CVE-2026-33017 (CVSS score: 9.3), is a case of missing authentication combined with code injection that could result in remote code execution. "The POST /api/v1
Mar 20, 2026·The Hacker News
Affected product
LA
langflow
langflow-ai
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