What is CVE-2021-43929?

CVE-2021-43929 is a medium-severity vulnerability in Synology Diskstation Manager, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 6.5/10. Published 2022-02-07.

How severe is CVE-2021-43929?

Medium severity. CVSS v3 base score is 6.5 out of 10.

XSS in Synology Diskstation Manager

CVE-2021-43929

Improper neutralization of special elements in output used by a downstream component ('Injection') vulnerability in work flow management in Synology DiskStation Manager (DSM) before 7.0.1-42218-2 allows remote authenticated users to inject arbitrary web script or HTML via unspecified vectors.

Published 2022-02-07 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L.

EPSS exploit prediction

EPSS: 0.006 (46.4th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 46.4% 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

Synology Diskstation Manager
Synology Diskstation Manager (Dsm) — versions unspecified

Weakness classification (CWE)

References

www.synology.com/security/advisory/Synology_SA_22_01 (Vendor Advisory)

Frequently asked questions

What is CVE-2021-43929?: CVE-2021-43929 is a medium-severity vulnerability in Synology Diskstation Manager, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 6.5/10. Published 2022-02-07.
How severe is CVE-2021-43929?: Medium severity. CVSS v3 base score is 6.5 out of 10.