CVE-2021-39643

Local privilege escalation via unchecked return value

Published Dec 15, 2021 · Updated Aug 4, 2024

Elevation of privilege in Google Titan M2 Android kernel allows local users with System privileges to escalate without user interaction. The ic_startRetrieveEntryValue function in acropora/app/identity/ic.c continues identity-credential processing without validating a return value. Exploitation requires existing System execution privileges; Google has not disclosed the crossed protection boundary or resulting higher privilege.

CVSS severity6.7
Medium
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Elevation of privilege in Google Titan M2 Android kernel allows local users with System privileges to escalate without user interaction. The ic_startRetrieveEntryValue function in acropora/app/identity/ic.c continues identity-credential processing without validating a return value. Exploitation requires existing System execution privileges; Google has not disclosed the crossed protection boundary or resulting higher privilege.

The record

CVE
CVE-2021-39643
Published
Dec 15, 2021
Updated
Aug 4, 2024
Vendor
Google
Product
Titan M2
Classifications
CWE-252, T1404
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Dec 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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=Android kernel

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Google · Titan M2version=Android kernel

Published CVSS scores

4.6NIST NVDAV:L/AC:L/Au:N/C:P/I:P/A:P
6.7NIST NVDCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-252Unchecked Return Value
T1404Exploitation 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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