Medium severity · published Apr 20, 2026
CVE-2026-6599
langflow-ai langflow Model Context Protocol Configuration API mcp_projects.py install_mcp_config injection
6.3
CVSS
0.2%
EPSS
No
On KEV
Description
A vulnerability was detected in langflow-ai langflow up to 1.8.3. The impacted element is the function get_client_ip/install_mcp_config of the file src/backend/base/langflow/api/v1/mcp_projects.py of the component Model Context Protocol Configuration API. Performing a manipulation of the argument X-Forwarded-For results in injection. The attack may be initiated remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 14% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LA
langflow · langflow-ai
1.8.0; 1.8.1; 1.8.2; 1.8.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-6599
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-6599
gist.github.com
https://gist.github.com/chenhouser2025/a909c47316b7a0948ee68c109ab747a3
vuldb.com
https://vuldb.com/submit/791922
vuldb.com
https://vuldb.com/vuln/358234
vuldb.com
https://vuldb.com/vuln/358234/cti
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