Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-77937— Letta through 0.16.8 Cross-Tenant Impersonation via user_id Header

Quick assessment

Affected
letta-ai letta
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Letta 0.16.8 版本存在一个身份验证绕过漏洞。该漏洞允许 API 调用者通过提供自声明的 HTTP 请求头来冒充其他用户。即使启用了 配置，攻击者仍可将 设置为其他租户的 ID，从而读取和修改该用户的智能体（agents）、记忆（memory）及配置信息。

CVSS 8.1 · High
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-77937

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Letta through 0.16.8 Cross-Tenant Impersonation via user_id Header
Source: CVE Program / CVE List V5
Vulnerability 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.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
通过用户控制密钥绕过授权机制
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
letta-ai letta 0 ~ 0.16.8 -

II. Public POCs for CVE-2026-77937

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-77937

请登录查看更多情报信息。

Other References for CVE-2026-77937 (3)

Same Patch Batch · letta-ai · 2026-10-20 · 3 CVEs total

CVE-2026-77936 9.8 CRITICAL Letta through 0.16.8 Insecure Default Configuration Unauthenticated API and PostgreSQL Acc
CVE-2026-77938 6.5 MEDIUM Letta through 0.16.8 Credential Exposure via Tool Sandbox Environment Inheritance

IV. Related Vulnerabilities

Same product: letta
Same vendor: letta-ai
Same weakness: CWE-639

V. Comments for CVE-2026-77937

No comments yet

Leave a comment