CVE-2026-77936

Letta through 0.16.8 ships a compose.yaml that does not enable LETTA_SERVER_SECURE, so the password middleware is never added and all API routes are unauthenticated, and it exposes a superuser PostgreSQL port with default credentials. Remote attackers can execute arbitrary Python via POST /v1/tools/run, manage /v1/admin users, or run OS commands via COPY PROGRAM.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/compose.yaml#L17
https://github.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/letta/server/rest_api/app.py#L799
https://www.lasso.security/vulnerability-database/cve-2026-77936
https://www.vulncheck.com/advisories/letta-through-0.16.8-insecure-default-configuration-unauthenticated-api-and-postgresql-access

Configurations

No configuration.

History

20 Oct 2026, 01:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-20 01:17

Updated : 2026-10-20 20:06

NVD link : CVE-2026-77936

Mitre link : CVE-2026-77936

CVE.ORG link : CVE-2026-77936

JSON object : View

Products Affected

No product.

CWE

CWE-1188

Initialization of a Resource with an Insecure Default

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