CVE-2021-34343

Buffer Overflow Vulnerability in QTS, QuTS hero, and QuTScloud

HIGH

7.2

CVSS Score

Published: September 10, 2021 at 04:00 AM UTC

Updated: June 17, 2026 at 03:55 AM UTC

3 products affected across 1 vendorQTSQuTS heroQuTScloud

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Severity

HIGH7.2

Exploit prediction

EPSS 2%

Description

A stack buffer overflow vulnerability has been reported to affect QNAP device running QTS, QuTScloud, QuTS hero. If exploited, this vulnerability allows attackers to execute arbitrary code. We have already fixed this vulnerability in the following versions of QTS, QuTScloud, QuTS hero: QTS 4.5.4.1715 build 20210630 and later QTS 5.0.0.1716 build 20210701 and later QuTScloud c4.5.6.1755 and later QuTS hero h4.5.4.1771 build 20210825 and later

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

QTS · Qnap

95%

v < 4.3.3.1693v < 4.5.4.1715 build 20210630v < 5.0.0.1716 build 202107014.3.4 ≤ v < 4.3.6.17504.4.0 ≤ v < 4.5.4.17155.0.0 ≤ v < 5.0.0.1716

Affected range stops below 4.3.3.1693, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.3.6.1750, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.5.4.1715, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.5.4.1715 build 20210630, so it looks safe — our inference, not a vendor statement

Affected range stops below 5.0.0.1716, so it looks safe — our inference, not a vendor statement

Affected range stops below 5.0.0.1716 build 20210701, so it looks safe — our inference, not a vendor statement

QuTS hero · Qnap

95%

v < h4.5.4.1771v < h4.5.4.1771 build 20210825

Affected range stops below h4.5.4.1771, so it looks safe — our inference, not a vendor statement

Affected range stops below h4.5.4.1771 build 20210825, so it looks safe — our inference, not a vendor statement

QuTScloud · Qnap

95%

v < c4.5.6.1755

Affected range stops below c4.5.6.1755, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://www.qnap.com/en/security-advisory/qsa-21-33

References (1)

x_refsource_MISCVendor Advisory

Source: [email protected]

https://www.qnap.com/en/security-advisory/qsa-21-33

CVSS

7.2HIGH[email protected]

Attack Vector: NETWORK
Complexity: LOW
Privileges: HIGH
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: HIGH
Integrity: HIGH
Availability: HIGH

Vector?

Quick Info

StatusMODIFIED

CWE

CWE-787

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