by Kastro
Paper/Archive/CVE-2026-77936

CVE-2026-77936

letta-ai letta — Letta through 0.16.8 Insecure Default Configuration Unauthenticated API and PostgreSQL Access

EPSS 0.6%public exploitCVSS 9.8
critical.is priorityof 100
49
CVSS 9.8 (CNA)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 48.1.481 × 209.6Exploit: SSVC poc+1010.0SSVC exploitation: poc+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
letta≤ 0.16.8–CNA

Scores by source

VulnCheck (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
VulnCheck (CNA)9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CISA ADPSSVCExploitation: poc · Automatable: yes · Technical impact: total

References

exploitlasso.security/vulnerability-database/cve-2026-77936writeupgithub.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/compose.yaml#L17writeupgithub.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/letta/server/rest_api/app.py#L799writeupvulncheck.com/advisories/letta-through-0.16.8-insecure-default-configuration-unauthenticated-api-and-postgresql-access