SSRF in Letta

CVE-2026-4964

A security vulnerability has been detected in letta-ai letta 0.16.4. This vulnerability affects the function _convert_message_create_to_message of the file letta/helpers/message_helper.py of the component File URL Handler. Such manipulation of the argument ImageContent leads to server-side request forgery. It is possible to launch the attack remotely. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Vulnerability class: SSRF (Server-Side Request Forgery)

EPSS: 0.003 (25.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/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-2026-4964?
CVE-2026-4964 is a medium-severity vulnerability in Letta, classified under Server-Side Request Forgery (SSRF). CVSS score: 6.3/10. Published 2026-03-27.
How severe is CVE-2026-4964?
Medium severity. CVSS v3 base score is 6.3 out of 10.