CVE-2026-77936criticalCWE-1188

CVE-2026-77936: critical vulnerability in letta-ai letta

Letta through 0.16.8 Insecure Default Configuration Unauthenticated API and PostgreSQL Access

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48Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 9.3epss 0.6%
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
letta-ai · letta
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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