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.

Published: 2017-08-14 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-11156 is rated Moderate Risk (59.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.30%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2017-11156

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-07-01 2.21% 2.30% +0.09%
2 2026-06-15 0.80% 2.21% +1.41%
3 2026-04-17 — 0.80% —

Full EPSS history (18 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-11156

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.0 HIGH
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]
6.5 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.0 6.4 [email protected]

Weakness enumeration for CVE-2017-11156

Affected software / configurations for CVE-2017-11156

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

References for CVE-2017-11156

cvelogic Threat Intelligence