What is CVE-2021-38678?

CVE-2021-38678 is a medium-severity vulnerability in QNAP Qcalagent, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 6.1/10. Published 2022-01-14.

How severe is CVE-2021-38678?

Medium severity. CVSS v3 base score is 6.1 out of 10.

Open Redirect in QNAP Qcalagent

CVE-2021-38678

An open redirect vulnerability has been reported to affect QNAP device running QcalAgent. If exploited, this vulnerability allows attackers to redirect users to an untrusted page that contains malware. We have already fixed this vulnerability in the following versions of QcalAgent: QcalAgent 1.1.7 and later

Vulnerability class: Open Redirect

Published 2022-01-14 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.006 (45.0th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 45.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

QNAP Qcalagent
QNAP Systems Inc. Qcalagent — versions unspecified

Weakness classification (CWE)

CWE-601 — URL Redirection to Untrusted Site (Open Redirect)

References

www.qnap.com/en/security-advisory/qsa-21-60 (Vendor Advisory)

Frequently asked questions

What is CVE-2021-38678?: CVE-2021-38678 is a medium-severity vulnerability in QNAP Qcalagent, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 6.1/10. Published 2022-01-14.
How severe is CVE-2021-38678?: Medium severity. CVSS v3 base score is 6.1 out of 10.