How severe is CVE-2021-29086?

CVE-2021-29086 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-29086 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-29086?

CVE-2021-29086 primarily affects Synology Diskstation Manager. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-29086?

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

When was CVE-2021-29086 published?

CVE-2021-29086 was published on 2021-06-23 and last updated on 2026-06-17.

CVE-2021-29086

CVE-2021-29086 is a medium-severity vulnerability in Synology Diskstation Manager with a CVSS 3.x base score of 5.3. 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-200.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Synology Diskstation Manager
Published: 2021-06-23
Last modified: 2026-06-17

Description

Exposure of sensitive information to an unauthorized actor vulnerability in webapi component in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows remote attackers to obtain sensitive information via unspecified vectors.

Frequently asked questions

What is CVE-2021-29086?: Exposure of sensitive information to an unauthorized actor vulnerability in webapi component in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows remote attackers to obtain sensitive information via unspecified vectors.
How severe is CVE-2021-29086?: CVE-2021-29086 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-29086 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-29086?: CVE-2021-29086 primarily affects Synology Diskstation Manager. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-29086?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-29086 published?: CVE-2021-29086 was published on 2021-06-23 and last updated on 2026-06-17.

References

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

Affected products (2)

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

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