Cyber Resilience

CVE-2026-30857

Access Control in Tencent Weknora ≤ 0.3.0

Public PoCAccess Control
Published
07 March 2026
Modified
09 March 2026
Patch / advisory
CVSS Score v3.1 5.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0022 13th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-30857 is a medium-severity Authorization Bypass Through User-Controlled Key (CWE-639) vulnerability in Tencent Weknora. Its CVSS base score is 5.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data from Information Repositories (T1213); ranked at the 13th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

This vulnerability is AI-related — categorised as LLM Application Platforms; in the Privacy and Disclosure risk domain.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-4 (Information Flow Enforcement) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

WeKnora is an LLM-powered framework designed for deep document understanding and semantic retrieval. Prior to version 0.3.0, a cross-tenant authorization bypass in the knowledge base copy endpoint allows any authenticated user to clone (duplicate) another tenant’s knowledge base into their…

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own tenant by knowing/guessing the source knowledge base ID. This enables bulk data exfiltration (document/FAQ content) across tenants. This issue has been patched in version 0.3.0.

CWE(s)

AI Security AnalysisAI

AI Category
LLM Application Platforms
Risk Domain
Privacy and Disclosure
OWASP Top 10 for LLMs 2025
None mapped
Classification Reason
Matched keywords: llm

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1213 Data from Information Repositories Collection
Adversaries may leverage information repositories to mine valuable information.
T1530 Data from Cloud Storage Collection
Adversaries may access data from cloud storage.
Why these techniques?

Authz bypass (IDOR on KB ID) directly enables unauthorized access and bulk collection/exfiltration of data from multi-tenant knowledge-base repositories or cloud storage.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-30247Same product: Tencent Weknora
CVE-2026-8786Same product: Tencent Weknora
CVE-2026-30855Same product: Tencent Weknora
CVE-2026-30860Same product: Tencent Weknora
CVE-2026-30859Same product: Tencent Weknora
CVE-2026-22687Same product: Tencent Weknora
CVE-2026-30856Same product: Tencent Weknora
CVE-2026-30861Same product: Tencent Weknora
CVE-2025-11046Same product: Tencent Weknora
CVE-2026-22688Same product: Tencent Weknora

Affected Assets

tencent
weknora
≤ 0.3.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • AC-4 Information Flow Enforcement
  • AC-6 Least Privilege
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces tenant-scoped authorization checks on the knowledge-base copy endpoint to block cross-tenant cloning by ID.

prevent

Enforces information-flow policy that prohibits any data movement from one tenant's knowledge base to another.

prevent

Restricts the copy operation to only those principals explicitly authorized for cross-tenant actions, reducing the attack surface.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 full match
prevents

Enforcing authorization policy and least privilege directly blocks user-controlled key tampering that bypasses access checks.

PR.IR-01 mostly match
prevents

Logical access controls prevent unauthorized data access that results from missing authorization checks on object references.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing can detect missing authorization checks but does not prevent the weakness in production.

prevents

Information access restriction explicitly enforces that users may only retrieve data they are authorized to see, directly addressing user-controlled key bypass.

prevents

Access control policy directly requires enforcement of authorization rules that prevent unauthorized access via manipulated keys.

prevents

Managing access rights includes ensuring users can only access their own records and not bypass authorization by altering identifiers.

mitigates

Privileged access rights control restricts what data each user may access, mitigating direct object reference attacks.

prevents

Secure development lifecycle includes authorization design but does not itself implement runtime access checks.

References