Medium severity · published Oct 20, 2026
CVE-2026-77938
Letta through 0.16.8 Credential Exposure via Tool Sandbox Environment Inheritance
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 36% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LE
letta · letta-ai
through 0.16.8 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-77938
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-77938
github.com
https://github.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/letta/services/tool_sandbox/base.py#L487
www.lasso.security
https://www.lasso.security/vulnerability-database/cve-2026-77938
www.vulncheck.com
https://www.vulncheck.com/advisories/letta-through-0.16.8-credential-exposure-via-tool-sandbox-environment-inheritance
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