CVE-2026-77938

Letta through 0.16.8 contains an information disclosure vulnerability that allows users running tools to read server secrets because LocalSandbox subprocesses inherit the full server environment. Attackers can run code via POST /v1/tools/run or custom tools to read LETTA_PG_URI, POSTGRES_PASSWORD, and provider API keys, then access cross-tenant database data.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/letta/services/tool_sandbox/base.py#L487
https://www.lasso.security/vulnerability-database/cve-2026-77938
https://www.vulncheck.com/advisories/letta-through-0.16.8-credential-exposure-via-tool-sandbox-environment-inheritance

Configurations

No configuration.

History

20 Oct 2026, 01:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-20 01:17

Updated : 2026-10-20 20:11

NVD link : CVE-2026-77938

Mitre link : CVE-2026-77938

CVE.ORG link : CVE-2026-77938

JSON object : View

Products Affected

No product.

CWE

CWE-526

Cleartext Storage of Sensitive Information in an Environment Variable

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