CVE-2026-77936

CVSS 9.8 (critical) · published 2026-10-20

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.

Weakness: CWE-1188

Source: NVD CVE-2026-77936

References

• 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

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