How severe is CVE-2021-43929?

CVE-2021-43929 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2021-43929 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43929?

CVE-2021-43929 affects Synology Diskstation Manager. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43929?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-43929 published?

CVE-2021-43929 was published on 2022-02-07 and last updated on 2026-06-17.

CVE-2021-43929

CVE-2021-43929 is a medium-severity vulnerability in Synology Diskstation Manager with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Synology Diskstation Manager
Published: 2022-02-07
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2021-43929?: CVE-2021-43929 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2021-43929 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43929?: CVE-2021-43929 affects Synology Diskstation Manager. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43929?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-43929 published?: CVE-2021-43929 was published on 2022-02-07 and last updated on 2026-06-17.

References

https://www.synology.com/security/advisory/Synology_SA_22_01

Affected products (1)

cpe:2.3:o:synology:diskstation_manager:*:*:*:*:*:*:*:*

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