CVE-2026-40966 | VectorStoreChatMemoryAdvisor conversation scoping can lead to cross-tenant memory exfiltration

In Spring AI, an attacker can bypass conversation isolation and exfiltrate sensitive memory from other users’ chat histories, including secrets and credentials, by injecting filter logic through conversationId. Only applications that use VectorStoreChatMemoryAdvisor and pass user-supplied input as a conversationId are affected.

Published: 2026-04-28 Last update: 2026-04-29 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-40966 is rated Low Risk (28.6/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.23%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-40966

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.05% 0.23% +0.18%
2 2026-05-30 0.04% 0.05% +0.02%
3 2026-04-28 — 0.04% —

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-40966

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 3.6 [email protected]

Weakness enumeration for CVE-2026-40966

GitHub Security Advisory for CVE-2026-40966

GHSA-v6x6-pjxw-3pv2 · Severity: medium · Ecosystem: maven — Spring AI's VectorStoreChatMemoryAdvisor conversation scoping can lead to cross-tenant memory exfiltration

Affected software / configurations for CVE-2026-40966

Vendor Product Version Raw CPE
vmware spring_ai >= 1.0.0, < 1.0.6 cpe:2.3:a:vmware:spring_ai:*:*:*:*:*:*:*:*
vmware spring_ai >= 1.1.0, < 1.1.5 cpe:2.3:a:vmware:spring_ai:*:*:*:*:*:*:*:*

References for CVE-2026-40966

cvelogic Threat Intelligence