What is CVE-2023-23363?

CVE-2023-23363 is a high-severity vulnerability in QNAP Qts, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 8.1/10. Published 2023-09-22.

How severe is CVE-2023-23363?

High severity. CVSS v3 base score is 8.1 out of 10.

Buffer overflow in QNAP Qts

CVE-2023-23363

A buffer copy without checking size of input vulnerability has been reported to affect QNAP operating system. If exploited, the vulnerability possibly allows remote users to execute code via unspecified vectors. We have already fixed the vulnerability in the following versions: QTS 4.3.6.2441 build 20230621 and later QTS 4.3.3.2420 build 20230621 and later QTS 4.2.6 build 20230621 and later QTS 4.3.4.2451 build 20230621 and later

Vulnerability class: Buffer Overflow

Published 2023-09-22 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.009 (58.8th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 59th percentile — 58.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.009 · change: +0.002

Affected products

QNAP Qts
QNAP Systems Inc. Qts — versions 4.3.*, 4.2.*, 4.5.*

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

www.qnap.com/en/security-advisory/qsa-23-25 (Vendor Advisory)

Frequently asked questions

What is CVE-2023-23363?: CVE-2023-23363 is a high-severity vulnerability in QNAP Qts, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 8.1/10. Published 2023-09-22.
How severe is CVE-2023-23363?: High severity. CVSS v3 base score is 8.1 out of 10.