CVE-2026-6599 json
langflow-ai langflow Model Context Protocol Configuration API mcp_projects.py install_mcp_config injection
published 6mo ago modified 3mo ago also GHSA-v66p-f7x3-4794 , PYSEC-2026-2569 , EUVD-2026-23762
- cvss
- 6.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 14%
- public exploits
- 0
- none known
Summary
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.
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Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 6mo ago
Exploit prediction
0.23% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-11).
Exploits and checks
- gist.github.com https://gist.github.com/chenhouser2025/a909c47316b7a0948ee68c109ab747a3 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P |
| CNA | 3.1 | 6.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:W/RC:R |
| CNA | 3.0 | 6.3 | CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:W/RC:R |
| CNA | 2.0 | 6.5 | AV:N/AC:L/Au:S/C:P/I:P/A:P/E:POC/RL:W/RC:UR |
| CNA | 4.0 | 2.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| CNA | 3.1 | 6.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L |
| CNA | 2.0 | 6.5 | AV:N/AC:L/Au:S/C:P/I:P/A:P |
| GitHub | 3.1 | 6.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L |
| OSV | 3.1 | 6.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | langflow | <=1.8.3 |
no fix listed |
Affected products
- langflow-ai langflow
Classification
References
-
gist.github.com
/chenhouser2025/a909c47316b7a0948ee68c109ab747a3
exploit, web
-
vuldb.com
/vuln/358234
vdb-entry, technical-description, web
-
vuldb.com
/vuln/358234/cti
signature, permissions-required, web
-
vuldb.com
/submit/791922
third-party-advisory, web
-
nvd.nist.gov
/vuln/detail/CVE-2026-6599
advisory
-
github.com
/langflow-ai/langflow
package
-
pypi.org
/project/langflow
package
-
github.com
/advisories/GHSA-v66p-f7x3-4794
advisory
Sources
- CVE List CVE-2026-6599
- GitHub Advisory GHSA-v66p-f7x3-4794
- NVD CVE-2026-6599
- OSV PYSEC-2026-2569
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.