How severe is CVE-2017-11156?

CVE-2017-11156 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2017-11156 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-11156?

CVE-2017-11156 primarily affects Synology Download Station. In total, 33 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-11156?

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-2017-11156 published?

CVE-2017-11156 was published on 2017-08-14 and last updated on 2026-06-17.

CVE-2017-11156

CVE-2017-11156 is a high-severity vulnerability in Synology Download Station with a CVSS 3.x base score of 7.8. 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-732.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 6.5
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-732
Affected product: Synology Download Station
Published: 2017-08-14
Last modified: 2026-06-17

Description

Synology Download Station 3.8.x before 3.8.5-3475 and 3.x before 3.5-2984 uses weak permissions (0777) for ui/dlm/btsearch directory, which allows remote authenticated users to execute arbitrary code by uploading an executable via unspecified vectors.

Frequently asked questions

What is CVE-2017-11156?: Synology Download Station 3.8.x before 3.8.5-3475 and 3.x before 3.5-2984 uses weak permissions (0777) for ui/dlm/btsearch directory, which allows remote authenticated users to execute arbitrary code by uploading an executable via unspecified vectors.
How severe is CVE-2017-11156?: CVE-2017-11156 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2017-11156 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-11156?: CVE-2017-11156 primarily affects Synology Download Station. In total, 33 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-11156?: 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-2017-11156 published?: CVE-2017-11156 was published on 2017-08-14 and last updated on 2026-06-17.

References

https://www.synology.com/en-global/support/security/Synology_SA_17_28_Download_Station

Affected products (33)

cpe:2.3:a:synology:download_station:3.2-2295:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.3-2382:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.3-2383:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.3-2386:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.4-2477:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.4-2478:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.4-2480:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.4-2485:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.4-2486:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.4-2489:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.4-2490:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.4-2514:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.4-2555:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.4-2557:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.4-2558:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2638:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2705:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2706:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2955:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2956:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2962:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2963:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2967:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2968:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2970:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2973:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2980:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.5-2982:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.8.0-3416:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.8.1-3420:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.8.2-3455:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.8.3-3458:*:*:*:*:*:*:*
cpe:2.3:a:synology:download_station:3.8.4-3468:*:*:*:*:*:*:*

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