CVE-2026-77937

8.1 HIGHpublic exploit available

Published 2026-10-20 · Updated 2026-10-20

AI analysis for this CVE has not been generated yet. Raw NVD data is shown below.

NVD description

Letta through 0.16.8 contains an authentication bypass vulnerability that allows API callers to impersonate other users by supplying a self-asserted user_id HTTP header. Attackers can set user_id to another tenant's ID, even with LETTA_SERVER_SECURE enabled, to read and modify that user's agents, memory and configuration.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Weaknesses

CWE-639

Public exploit & PoC references

https://github.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/letta/server/rest_api/dependencies.py#L39

All references

https://github.com/letta-ai/letta/blob/1131535716e8a31c9a437f8695e25ac98f203a24/letta/server/rest_api/dependencies.py#L39
https://www.lasso.security/vulnerability-database/cve-2026-77937
https://www.vulncheck.com/advisories/letta-through-0.16.8-cross-tenant-impersonation-via-user-id-header

Source data: NVD (nvd.nist.gov), public domain. Exploit-DB.ai adds local AI analysis for defensive use only.

Related CVEs

CRITICALCVE-2024-34323
MEDIUMCVE-2025-71420PoC
UNSCOREDCVE-2026-100177PoC
HIGHCVE-2026-100268
MEDIUMCVE-2026-100272
HIGHCVE-2026-100514
HIGHCVE-2026-100517
MEDIUMCVE-2026-100531PoC

Related by shared AI tags and CWE weakness class. Browse the full archive.