CVE-2021-3675

Enclave crash via heap allocation header overwrite

Published Jun 16, 2022 · Updated Sep 16, 2024

Improper input validation in Synaptics Fingerprint Driver allows local users to disclose protected enclave data through a crafted command. The synaTEE.signed.dll SGX API mishandles the command and overwrites the upper 32 bits of a 64-bit-token-guarded heap allocation header. Exploitation requires a local low-privileged host application; Synaptics verified the header overwrite and a crash when the block is freed, but did not confirm code execution.

CVSS severity5.5
Medium
EPSS probability0.26%
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 Synaptics Fingerprint Driver allows local users to disclose protected enclave data through a crafted command. The synaTEE.signed.dll SGX API mishandles the command and overwrites the upper 32 bits of a 64-bit-token-guarded heap allocation header. Exploitation requires a local low-privileged host application; Synaptics verified the header overwrite and a crash when the block is freed, but did not confirm code execution.

The record

CVE
CVE-2021-3675
Published
Jun 16, 2022
Updated
Sep 16, 2024
Vendor
Synaptics Incorporated
Product
Synaptics Fingerprint Driver
Classifications
CWE-20, CWE-787
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 16, 2022CVE 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=5.1.xxx.26 <xxx=340
  2. Affected versionversion=5.2.2xx.26 <xx=29
  3. Affected versionversion=5.2.3xx.26 <xx=25
  4. Affected versionversion=5.2.xxxx.26 <xxxx=3541
  5. Affected versionversion=5.3.xxxx.26 <xxxx=3543
  6. Affected versionversion=5.5.xx.1058 <xx=44
  7. Affected versionversion=5.5.xx.1102 <xx=34
  8. Affected versionversion=5.5.xx.1116 <xx=14
  9. Affected versionversion=6.0.xx.1104 <xx=50
  10. Affected versionversion=6.0.xx.1108 <xx=31
  11. Affected versionversion=6.0.xx.1111 <xx=58

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Synaptics Incorporated · Synaptics Fingerprint Driverversion=5.1.xxx.26 <xxx=340; version=5.2.2xx.26 <xx=29; version=5.2.3xx.26 <xx=25; version=5.2.xxxx.26 <xxxx=3541; version=5.3.xxxx.26 <xxxx=3543; version=5.5.xx.1058 <xx=44; version=5.5.xx.1102 <xx=34; version=5.5.xx.1116 <xx=14; version=6.0.xx.1104 <xx=50; version=6.0.xx.1108 <xx=31; version=6.0.xx.1111 <xx=58

Published CVSS scores

5.5Synaptics, Inc.CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
7.1NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/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.

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-20Improper Input Validation
CWE-787Out-of-bounds Write

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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