CVE-2026-77936
Letta through 0.16.8 Insecure Default Configuration Unauthenticated API and PostgreSQL Access
- State
- Published
- Severity
- 9.3 Critical
- Published
- Oct 20, 2026
- Updated
- Oct 20, 2026
- Reserved
- Aug 21, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 9.3 Critical | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N | VulnCheck |
| 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | VulnCheck |
Weaknesses
- CWE-1188 Initialization of a Resource with an Insecure Default
Affected Products
| Product | Versions |
|---|---|
lettaletta-ai |
|
References
- Lasso.security Advisorytechnical-descriptionexploit
- https://github.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/compose.yaml#L17technical-description
- https://github.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/letta/server/rest_api/app.py#L799technical-description
- VulnCheck Advisory: Letta through 0.16.8 Insecure Default Configuration Unauthenticated API and PostgreSQL Accessthird-party-advisory
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