CVE-2026-55255
published 2026-06-23CVE-2026-55255: Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, an Insecure Direct Object Reference (IDOR) vulnerability in…
PriorityP186high8.4CVSS 3.1
AVNACHPRLUINSCCHIHAL
KEVITWEXPLOIT
CISA Known Exploited Vulnerabilitydue 2026-07-10
Exploited in the wild
EPSS
29.05%
98.0th percentile
Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, an Insecure Direct Object Reference (IDOR) vulnerability in /api/v1/responses endpoint allows an authenticated attacker to execute any flow belonging to another user by specifying the victim's flow ID in the request. This vulnerability is fixed in 1.9.1.
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| langflow-ai | langflow | < 1.9.1 | 1.9.1 |
| langflow | langflow | < 1.9.1 | 1.9.1 |
| langflow | langflow | >= 0 < 1.9.1 | 1.9.1 |
Detection & IOCsextracted from sources · hover to see the quote
url/api/v1/responses
- →Monitor authenticated requests to /api/v1/responses where the flow ID in the request does not belong to the authenticated user — cross-user flow ID references indicate IDOR exploitation. ↗
- →Flag any authenticated session accessing /api/v1/responses with a flow ID that resolves to a different user's ownership record — this is the core authorization bypass mechanism. ↗
- ·Vulnerability only affects Langflow versions prior to 1.9.1; upgrade to 1.9.1 or later to remediate. CISA remediation deadline is 2026-07-10. ↗
- ·Exploitation requires an authenticated session — unauthenticated access alone is insufficient, but any valid account can abuse the endpoint against other users' flows. ↗
CVSS provenance
nvdv3.18.4HIGHCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:L
vulncheck9.9CRITICAL
cisa8.4HIGH
CVEs like this are exactly what “Exploited This Week” covers.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
VulDB
langflow-ai langflow up to 1.9.1 /api/v1/responses authorization (GHSA-qrpv-q767-xqq2)
vuldb·2026-06-24·CVSS 9.9
CVE-2026-55255 [CRITICAL] langflow-ai langflow up to 1.9.1 /api/v1/responses authorization (GHSA-qrpv-q767-xqq2)
A vulnerability, which was classified as critical, was found in langflow-ai langflow up to 1.9.1. This issue affects some unknown processing of the file /api/v1/responses. Executing a manipulation can lead to authorization bypass.
This vulnerability is tracked as CVE-2026-55255. The attack can be launched remotely. No exploit exists.
You should upgrade the affected component.
GHSA
Langflow: IDOR Vulnerability in `/api/v1/responses` Endpoint Allows Authenticated Attackers to Access Another User's Flow
ghsa·2026-06-19
CVE-2026-55255 [CRITICAL] CWE-639 Langflow: IDOR Vulnerability in `/api/v1/responses` Endpoint Allows Authenticated Attackers to Access Another User's Flow
Langflow: IDOR Vulnerability in `/api/v1/responses` Endpoint Allows Authenticated Attackers to Access Another User's Flow
## Summary
Insecure Direct Object Reference (IDOR) vulnerability in `/api/v1/responses` endpoint allows an authenticated attacker to execute any flow belonging to another user by specifying the victim's flow ID in the request.
## Details
The vulnerability exists in the `get_flow_by_id_or_endpoint_name` helper function in [`src/backend/base/langflow/helpers/flow.py` (lines 399-414)](https://github.com/langflow-ai/langflow/blob/v1.9.0/src/backend/base/langflow/helpers/flow.py#L399C1-L414C67).
When a flow is accessed via UUID (flow_id), the function queries the database directly without verifying if the authenticated user owns that flow:
```python
# src/backend/base/
VulnCheck
langflow langflow Authorization Bypass Through User-Controlled Key
vulncheck·2026·CVSS 9.9
CVE-2026-55255 [CRITICAL] langflow langflow Authorization Bypass Through User-Controlled Key
langflow langflow Authorization Bypass Through User-Controlled Key
Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.2, an Insecure Direct Object Reference (IDOR) vulnerability in /api/v1/responses endpoint allows an authenticated attacker to execute any flow belonging to another user by specifying the victim's flow ID in the request. This vulnerability is fixed in 1.9.2.
Affected: langflow langflow
Required Action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Exploitation References: https://webflow.sysdig.com/blog/understanding-langflow-cve-2026-55255-and-why-higher-cvss-vulnerabilities-arent-always-the-most-exploited
CISA
Langflow Authorization Bypass Through User-Controlled Key Vulnerability
cisa·2026-07-07·CVSS 8.4
CVE-2026-55255 [HIGH] CWE-639 Langflow Authorization Bypass Through User-Controlled Key Vulnerability
Vulnerability: Langflow Authorization Bypass Through User-Controlled Key Vulnerability
Affected: Langflow Langflow
Langflow contains an authorization bypass through user-controlled key vulnerability which allows an authenticated attacker to execute any flow belonging to another user by specifying the victim's flow ID in the request.
Required Action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring a
No detection rules found.
No public exploits indexed.
Hackernews
New ENCFORGE Ransomware Targets AI Model Files in Langflow RCE Attack
blogs_hackernews·2026-07-21·CVSS 9.8
CVE-2025-3248 [CRITICAL] New ENCFORGE Ransomware Targets AI Model Files in Langflow RCE Attack
Home
Threat Intelligence
Vulnerabilities
Cyber Attacks
Webinars
Expert Insights
Awards
Webinars
Awards
Free eBooks
About THN
Jobs
Advertise with us
## New ENCFORGE Ransomware Targets AI Model Files in Langflow RCE Attack
Researchers at Sysdig have linked a second attack on the same Langflow server to JADEPUFFER , the AI-agent-driven operator it first documented earlier this month.
The same operator has now been spotted deploying ENCFORGE , a new compiled Go ransomware designed to encrypt model weights, vector indexes, training datasets, and other AI infrastructure files across the host filesystem.
/api/v1/validate/code
CVE-2025-3248
AES_ENCRYPT()
The new ENCFORGE payload replaces those improvised scripts with compiled tooling aimed at the model stores, vector databases
Hackernews
CISA Adds 4 Actively Exploited Adobe, Joomla, and Langflow Flaws to KEV
blogs_hackernews·2026-07-08·CVSS 10.0
CVE-2026-48282 [CRITICAL] CISA Adds 4 Actively Exploited Adobe, Joomla, and Langflow Flaws to KEV
Home
Threat Intelligence
Vulnerabilities
Cyber Attacks
Webinars
Expert Insights
Awards
Webinars
Awards
Free eBooks
About THN
Jobs
Advertise with us
## CISA Adds 4 Actively Exploited Adobe, Joomla, and Langflow Flaws to KEV
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Tuesday added four security flaws to its Known Exploited Vulnerabilities ( KEV ) catalog, citing evidence of active exploitation.
The vulnerabilities are listed below -
CVE-2026-48282 (CVSS score: 10.0) - A path traversal vulnerability in Adobe ColdFusion that could lead to arbitrary code execution in the context of the current user.
CVE-2026-56290 (CVSS score: 10.0) - An improper access control vulnerability in Joomlack Page Builder that could allow for remote code execution via unaut
Checkpoint
29th June – Threat Intelligence Report
blogs_checkpoint·2026-06-29
CVE-2026-20245 29th June – Threat Intelligence Report
Latest Publications
CPR Podcast Channel
AI Research
Web 3.0 Security
Intelligence Reports
ThreatCloud AI
Threat Intelligence & Research
Zero Day Protection
Sandblast File Analysis
About Us
SUBSCRIBE
2026
2025
2024
2023
2022
2021
2020
2019
2018
2017
2016
## 29th June – Threat Intelligence Report
For the latest discoveries in cyber research for the week of 29th June, please download our Threat Intelligence Bulletin.
TOP ATTACKS AND BREACHES
Polymarket, a large cryptocurrency-based prediction market, has confirmed a supply chain attack after a third-party frontend vendor breach led to malicious JavaScript being injected into its website. Attackers tricked users into approving fraudulent transactions, stealing about $3 million from fewer than 15 accounts, while the b
https://github.com/langflow-ai/langflow/commit/2c9f498d664a3c32698b57d7c5e752625291060ehttps://github.com/langflow-ai/langflow/pull/12832https://github.com/langflow-ai/langflow/security/advisories/GHSA-qrpv-q767-xqq2https://github.com/langflow-ai/langflow/security/advisories/GHSA-qrpv-q767-xqq2https://webflow.sysdig.com/blog/understanding-langflow-cve-2026-55255-and-why-higher-cvss-vulnerabilities-arent-always-the-most-exploitedhttps://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-55255
2026-06-23
Published
2026-07-07
Added to CISA KEV
Exploited in the wild