TI-2026-76659 Aliases CVE-2026-75128

Missing authentication in Langchain-Chatchat lets attackers run commands

HIGH 81CWE-306Published 2026-10-20 · Updated 2026-10-20

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: Security bypass
Confidentiality · integrity · availability: High · High · High
Fix status: No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-306.

Summary

Langchain-Chatchat through 0.3.1.3 exposes a POST /tools/call endpoint that invokes any registered tool by name without authentication. Remote unauthenticated attackers can run arbitrary OS commands on the server through the always-registered shell tool, as the server user (root in the shipped Docker image). A public exploit is linked in the references.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

Langchain-Chatchat through 0.3.1.3 exposes a POST /tools/call API endpoint that invokes any registered tool by name without authentication, leaving the always-registered shell tool callable. Remote attackers can send a single request naming the shell tool to execute arbitrary OS commands as the server user (root in the shipped Docker image).

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.02226 82nd percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by the CNA

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: Yes
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
chatchat-space	Langchain-Chatchat	up to 0.3.1.3	—	No fix listed	CNA

Langchain-Chatchat Vendorchatchat-space Affected up to 0.3.1.3 Fixed in — No fix listed CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:a:chatchat-space:langchain-chatchat::::::::	—	—	chatchat-space

cpe:2.3:a:chatchat-space:langchain-chatchat:*:*:*:*:*:*:*:* Versions — — ·chatchat-space

Remediation

The sources list no fixed version for Langchain-Chatchat.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Timeline

2026-10-20 Threatist record created from CVE-2026-75128
2026-10-20 CISA SSVC decision points changed
2026-10-20 Priority changed: MEDIUM → HIGH
2026-10-27 EPSS moved to the 50th–90th percentile

References

Exploit 1

Lasso.security Advisory

Other 1

https://github.com/chatchat-space/Langchain-Chatchat/blob/a6a9193b5002061719f0eee62c6310bd5b1b7f63/libs/chatchat-server/chatchat/server/api_server/tool_routes.py#L33

TI-2026-06902 chatchat-space Langchain-Chatchat Compatible File Service openai_routes.py delete_file missing authentication CVSS 4.0MEDIUM 5.3
TI-2025-06227 chatchat-space Langchain-Chatchat files path traversal CVSS 4.0MEDIUM 5.3
TI-2025-06226 chatchat-space Langchain-Chatchat Backend upload_temp_docs path traversal CVSS 4.0MEDIUM 5.3
TI-2025-06228 chatchat-space Langchain-Chatchat file path traversal CVSS 4.0MEDIUM 5.1
TI-2026-06905 chatchat-space Langchain-Chatchat Uploaded File openai_routes.py _get_file_id random values CVSS 4.0LOW 2.1
TI-2026-06904 chatchat-space Langchain-Chatchat OpenAI-Compatible File Upload API openai_routes.py files toctou CVSS 4.0LOW 2.1

See all 7 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences