CVE-2026-77938: Cleartext Storage of Sensitive Information in an Environment Variable in letta-ai letta
Description
Letta versions up to 0.16.8 have a vulnerability where sensitive server environment variables are exposed to subprocesses. This allows users running tools to read secrets such as database URIs, passwords, and API keys. The flaw arises because LocalSandbox subprocesses inherit the full server environment, enabling attackers to access cross-tenant data by executing code via specific endpoints.
CVSS v4.0
Score 7.1high
Affected software
letta-ai
letta
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-77938 describes an information disclosure vulnerability in letta through version 0.16.8. The vulnerability occurs because LocalSandbox subprocesses inherit the entire server environment, including sensitive environment variables like LETTA_PG_URI, POSTGRES_PASSWORD, and provider API keys. Attackers with the ability to run code via the POST /v1/tools/run endpoint or custom tools can exploit this to read these secrets and gain unauthorized access to cross-tenant database data.
Potential Impact
An attacker with limited privileges can read sensitive environment variables containing database credentials and API keys. This can lead to unauthorized access to cross-tenant data in the database, resulting in potential data leakage and compromise of multiple tenants' information.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict access to the POST /v1/tools/run endpoint and custom tools to trusted users only, and avoid running untrusted code in the LocalSandbox environment.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-08-21T17:52:36.080Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ad6c1992cdf04f656e4957b
Added to database: 10/20/2026, 01:19:21 UTC
Last enriched: 10/20/2026, 01:33:13 UTC
Last updated: 10/20/2026, 01:34:17 UTC
Views: 4
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.