CVE-2026-77936CWE-1188

CVE-2026-77936

Critical · published October 20, 2026

CVSS v3.1
9.8
EPSS
0%
Percentile
39.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
9.3 · 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
EPSS
0.00470 · 39.7th percentile
Weakness
CWE-1188 · Initialization of a Resource with an Insecure Default
Published
2026-10-20T05:17Z
References (4)
https://github.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/compose.yaml#L17 · [email protected]https://github.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/letta/server/rest_api/app.py#L799 · [email protected]https://www.lasso.security/vulnerability-database/cve-2026-77936 · [email protected]https://www.vulncheck.com/advisories/letta-through-0.16.8-insecure-default-configuration-unauthenticated-api-and-postgresql-access · [email protected]
EPSS history
Timeline
  • 21 OCT 03:32Z
    EPSS moved — → 0%
    epss
  • 20 OCT 00:46Z
    Letta through 0.16.8 Insecure Default Configuration Unauthenticated API and PostgreSQL Access
    cvelistv5
  • 20 OCT 00:46Z
    Letta through 0.16.8 Insecure Default Configuration Unauthenticated API and PostgreSQL Access
    cvelistv5