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TI-2026-04326 Aliases CVE-2026-4965GHSA-wmhq-7qrq-wwwj

letta-ai letta Incomplete Fix CVE-2025-6101 ast_parsers.py resolve_type eval injection

Priority HIGH 70CWE-94Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Code execution
Confidentiality · integrity · availability
Low · Low · Low
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-94.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00627 50th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA and NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
letta-ailetta0.16.4—No fix listedCNA
  • letta Vendorletta-ai Affected 0.16.4 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:letta:letta:0.16.4:*:*:*:*:*:*:*0.16.4VulnerableLetta
  • cpe:2.3:a:letta:letta:0.16.4:*:*:*:*:*:*:* Versions 0.16.4 Vulnerable ·Letta

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-4965
  2. 2026-10-03 Alias added: GHSA-wmhq-7qrq-wwwj
  3. 2026-10-25 EPSS moved to the below the 50th percentile
  4. 2026-10-30 EPSS moved to the 50th–90th percentile

References

Exploit 1

  • TI-2026-76666 Insecure default configuration in Letta exposes API and PostgreSQL CVSS 4.0CRITICAL 9.3
  • TI-2026-76667 Letta lets API callers impersonate other users via user_id header CVSS 4.0HIGH 8.6
  • TI-2026-15517 letta-ai LettaBot API Status Route server.ts missing authentication CVSS 4.0MEDIUM 6.9
  • TI-2026-76668 Letta tool sandbox exposes server secrets to tool users CVSS 4.0HIGH 7.1
  • TI-2025-05511 letta-ai letta interface.py function_message eval injection CVSS 4.0MEDIUM 5.1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences