CVE-2017-9855
** DISPUTED ** An issue was discovered in SMA Solar Technology products. A secondary...
An issue was discovered in SMA Solar Technology products. A secondary authentication system is available for Installers called the Grid Guard system. This system uses predictable codes, and a single Grid Guard code can be used on any SMA inverter. Any such code, when combined with the installer account, allows changing very sensitive parameters. NOTE: the vendor reports that Grid Guard is not an authentication feature; it is only a tracing feature. Also, only Sunny Boy TLST-21 and TL-21 and Sunny Tripower TL-10 and TL-30 could potentially be affected
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List
An issue was discovered in SMA Solar Technology products. A secondary authentication system is available for Installers called the Grid Guard system. This system uses predictable codes, and a single Grid Guard code can be used on any SMA inverter. Any such code, when combined with the installer account, allows changing very sensitive parameters. NOTE: the vendor reports that Grid Guard is not an authentication feature; it is only a tracing feature. Also, only Sunny Boy TLST-21 and TL-21 and Sunny Tripower TL-10 and TL-30 could potentially be affected
- Record
CVE-2017-9855- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-863
- Updated
- 2026-11-02
EUVDEUVD-2017-18765
An issue was discovered in SMA Solar Technology products. A secondary authentication system is available for Installers called the Grid Guard system. This system uses predictable codes, and a single Grid Guard code can be used on any SMA inverter. Any such code, when combined with the installer account, allows changing very sensitive parameters. NOTE: the vendor reports that Grid Guard is not an authentication feature; it is only a tracing feature. Also, only Sunny Boy TLST-21 and TL-21 and Sunny Tripower TL-10 and TL-30 could potentially be affected
- Record
EUVD-2017-18765- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-v4m3-hw9h-pqgx
** DISPUTED ** An issue was discovered in SMA Solar Technology products. A secondary...
** DISPUTED ** An issue was discovered in SMA Solar Technology products. A secondary authentication system is available for Installers called the Grid Guard system. This system uses predictable codes, and a single Grid Guard code can be used on any SMA inverter. Any such code, when combined with the installer account, allows changing very sensitive parameters. NOTE: the vendor reports that Grid Guard is not an authentication feature; it is only a tracing feature. Also, only Sunny Boy TLST-21 and TL-21 and Sunny Tripower TL-10 and TL-30 could potentially be affected.
- Record
GHSA-v4m3-hw9h-pqgx- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-284, CWE-863
- Updated
- 2026-11-02
NVD
An issue was discovered in SMA Solar Technology products. A secondary authentication system is available for Installers called the Grid Guard system. This system uses predictable codes, and a single Grid Guard code can be used on any SMA inverter. Any such code, when combined with the installer account, allows changing very sensitive parameters. NOTE: the vendor reports that Grid Guard is not an authentication feature; it is only a tracing feature. Also, only Sunny Boy TLST-21 and TL-21 and Sunny Tripower TL-10 and TL-30 could potentially be affected
- Record
CVE-2017-9855- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-863
- Updated
- 2026-11-02
Affected products
- sma sunny boy 1.5 firmware
- sma sunny boy 2.5 firmware
- sma sunny boy 3.0 firmware
- sma sunny boy 3.6 firmware
- sma sunny boy 3000tl firmware
- sma sunny boy 3600 firmware
- sma sunny boy 3600tl firmware
- sma sunny boy 4.0 firmware
- sma sunny boy 4000tl firmware
- sma sunny boy 5.0 firmware
- sma sunny boy 5000 firmware
- sma sunny boy 5000tl firmware
Show 27 moreShow less
- sma sunny boy storage 2.5 firmware
- sma sunny central 1000cp xt firmware
- sma sunny central 2200 firmware
- sma sunny central 500cp xt firmware
- sma sunny central 630cp xt firmware
- sma sunny central 720cp xt firmware
- sma sunny central 760cp xt firmware
- sma sunny central 800cp xt firmware
- sma sunny central 850cp xt firmware
- sma sunny central 900cp xt firmware
- sma sunny central storage 1000 firmware
- sma sunny central storage 2200 firmware
- sma sunny central storage 2500-ev firmware
- sma sunny central storage 500 firmware
- sma sunny central storage 630 firmware
- sma sunny central storage 720 firmware
- sma sunny central storage 760 firmware
- sma sunny central storage 800 firmware
- sma sunny central storage 850 firmware
- sma sunny central storage 900 firmware
- sma sunny tripower 12000tl firmware
- sma sunny tripower 15000tl firmware
- sma sunny tripower 20000tl firmware
- sma sunny tripower 25000tl firmware
- sma sunny tripower 5000tl firmware
- sma sunny tripower 60 firmware
- sma sunny tripower core1 firmware
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2017-9855 is a critical vulnerability (CVSS 9.8) in Sma Sunny Boy 1.5 Firmware, published August 5, 2017. Its validity is disputed. EPSS puts the chance of exploitation in the next 30 days at 1.58%, the 75th percentile.