RCE in Letta

CVE-2026-4965

A vulnerability was detected in letta-ai letta 0.16.4. This issue affects the function resolve_type of the file letta/functions/ast_parsers.py of the component Incomplete Fix CVE-2025-6101. Performing a manipulation results in improper neutralization of directives in dynamically evaluated code. The attack can be initiated remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Vulnerability class: RCE (Remote Code Execution)

EPSS: 0.006 (45.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.

Affected products

Weakness classification (CWE)

References

  • cna@vuldb.com (technical-description, VDB Entry, Third Party Advisory, vdb-entry)
  • cna@vuldb.com (signature, Permissions Required, permissions-required, VDB Entry)
  • cna@vuldb.com (Exploit, VDB Entry, Third Party Advisory, third-party-advisory)
  • cna@vuldb.com (Exploit, Third Party Advisory, exploit)

Frequently asked questions

What is CVE-2026-4965?
CVE-2026-4965 is a high-severity vulnerability in Letta, classified under Code Injection. CVSS score: 7.3/10. Published 2026-03-27.
How severe is CVE-2026-4965?
High severity. CVSS v3 base score is 7.3 out of 10.