CVE-2021-22550

Enclave memory overwrite via mutable pointer reread

Published Jun 8, 2021 · Updated Sep 16, 2024

Memory corruption in Google Asylo 0.6.1 and earlier allows local users to overwrite arbitrary memory inside an SGX enclave. UntrustedCacheMalloc::GetBuffer validates an entry in an untrusted pointer array, then rereads the mutable entry instead of retaining the validated value. A low-privilege local user must alter the entry between validation and use; successful exploitation corrupts protected enclave memory.

CVSS severity7.8
High
EPSS probability0.10%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory corruption in Google Asylo 0.6.1 and earlier allows local users to overwrite arbitrary memory inside an SGX enclave. UntrustedCacheMalloc::GetBuffer validates an entry in an untrusted pointer array, then rereads the mutable entry instead of retaining the validated value. A low-privilege local user must alter the entry between validation and use; successful exploitation corrupts protected enclave memory.

The record

CVE
CVE-2021-22550
Published
Jun 8, 2021
Updated
Sep 16, 2024
Vendor
Google
Product
Asylo
Classifications
CWE-668, CWE-823
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 8, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <=0.6.1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Google · Asyloversion=unspecified <=0.6.1

Published CVSS scores

4.6NIST NVDAV:L/AC:L/Au:N/C:P/I:P/A:P
7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.5Google LLCCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-668Exposure of Resource to Wrong Sphere
CWE-823Use of Out-of-range Pointer Offset

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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