How severe is CVE-2021-29083?

CVE-2021-29083 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-29083 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-29083?

CVE-2021-29083 affects Synology Diskstation Manager. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-29083?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-29083 published?

CVE-2021-29083 was published on 2021-04-01 and last updated on 2026-06-17.

CVE-2021-29083

CVE-2021-29083 is a high-severity vulnerability in Synology Diskstation Manager with a CVSS 3.x base score of 7.2. 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-78.

Key facts

Severity: High (CVSS 3.x base score 7.2)
CVSS v2: 9.0
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Synology Diskstation Manager
Published: 2021-04-01
Last modified: 2026-06-17

Description

Improper neutralization of special elements used in an OS command in SYNO.Core.Network.PPPoE in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows remote authenticated users to execute arbitrary code via realname parameter.

Frequently asked questions

What is CVE-2021-29083?: Improper neutralization of special elements used in an OS command in SYNO.Core.Network.PPPoE in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows remote authenticated users to execute arbitrary code via realname parameter.
How severe is CVE-2021-29083?: CVE-2021-29083 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-29083 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-29083?: CVE-2021-29083 affects Synology Diskstation Manager. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-29083?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-29083 published?: CVE-2021-29083 was published on 2021-04-01 and last updated on 2026-06-17.

References

https://www.synology.com/security/advisory/Synology_SA_20_26

Affected products (1)

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

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