CVE-2021-0186

Enclave compromise via unsafe exception re-entry

Published Nov 17, 2021 · Updated Aug 3, 2024

Improper input validation in Intel SGX SDK applications on SGX2 processors allows privileged local users to compromise enclaves. The exception handler permits asynchronous re-entry before enclave state is safely saved, letting a hostile operating system corrupt the trusted stack and control saved registers. Exploitation requires privileged control of local exception delivery and can disclose enclave memory or execute return-oriented code inside the enclave.

CVSS severity8.2
High
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Intel SGX SDK applications on SGX2 processors allows privileged local users to compromise enclaves. The exception handler permits asynchronous re-entry before enclave state is safely saved, letting a hostile operating system corrupt the trusted stack and control saved registers. Exploitation requires privileged control of local exception delivery and can disclose enclave memory or execute return-oriented code inside the enclave.

The record

CVE
CVE-2021-0186
Published
Nov 17, 2021
Updated
Aug 3, 2024
Vendor
Topcon Positioning Systems, Inc.
Product
Intel Software Guard Extensions SDK
Classifications
CWE-20, T1068
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Nov 17, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=See references

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Topcon Positioning Systems, Inc. · Intel Software Guard Extensions SDKversion=See references

Published CVSS scores

6.7NIST NVDCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
4.6NIST NVDAV:L/AC:L/Au:N/C:P/I:P/A:P
8.2Intel CorporationCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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