CVE-2026-59308

Semantic Cache Cross-Tenant Isolation Bypass via SHA-256 Truncation

Published Aug 21, 2026 CVSS 3.1 · 4.2 Medium EPSS < 1% KEV · Not listed
Description
In Spring AI's Semantic Cache support, the context hash used to isolate cached responses between different system prompts could allow cached responses to be shared across unrelated contexts.
Affected versions:
Spring AI: 2.0.0

Analysis

AI-generated

Technical impact

Spring AI does not separate cached responses for different system prompts as strictly as intended. The context hash, which is used to isolate cached replies, truncates a SHA‑256 value, creating the possibility that two unrelated prompts produce identical hashes. Because of this collision, a requester can retrieve a cached answer that was generated for a different context, exposing information that should have been isolated to the original tenant.

Affected Systems

Products affected are Spring AI version 2.0.0.

Risk and Exploitability

The CVSS score of 4.2 reflects a moderate risk. EPSS is not available and the vulnerability is not listed in the CISA KEV catalog, indicating no known widespread exploitation. The attack vector is inferred to involve normal usage of the Semantic Cache feature, which allows collision exploitation if an attacker can trigger identical truncated hashes for different tenant contexts.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Upgrade Spring AI to the latest patched release that addresses the truncated hash collision bug.
  • If an immediate upgrade is not possible, disable the Semantic Cache feature or limit its use to single‑tenant contexts until the fix is available.
  • Review and reinforce tenant‑specific context handling in the application code to ensure cached data is never shared across unrelated tenants.

Generated by OpenCVE AI on August 21, 2026 at 13:40 UTC.

Tracking

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Advisories

No advisories available
References
History
Type Values Removed Values Added
First Time appeared Vmware
Vmware spring Ai
CPEs cpe:2.3:a:vmware:spring_ai:*:-:*:*:*:*:*:*
Vendors & Products Vmware
Vmware spring Ai
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Spring
Spring spring Ai
Vendors & Products Spring
Spring spring Ai
Type Values Removed Values Added
Description In Spring AI's Semantic Cache support, the context hash used to isolate cached responses between different system prompts could allow cached responses to be shared across unrelated contexts. Affected versions: Spring AI: 2.0.0
Title Semantic Cache Cross-Tenant Isolation Bypass via SHA-256 Truncation
Weaknesses CWE-668
References
Metrics cvssV3_1

{'score': 4.2, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N'}

Weaknesses
  • CWE-668

    Exposure of Resource to Wrong Sphere

Sources

Status
PUBLISHED
Assigner
vmware
Published
Updated
Aug 21, 2026, 2:29 PM
Reserved
Jul 4, 2026, 6:13 PM
Status
Analyzed
Published
Aug 21, 2026, 12:16 PM
Modified
Oct 16, 2026, 3:10 PM