CVE-2017-9857 [High] | Authentication Bypass in Sunny Boy 3600 Firmware

An issue was discovered in SMA Solar Technology products. The SMAdata2+ communication protocol does not properly use authentication with encryption: it is vulnerable to man in the middle, packet injection, and replay attacks. Any setting change, authentication packet, scouting packet, etc. can be replayed, injected, or used for a man in the middle session. All functionalities available in Sunny Explorer can effectively be done from anywhere within the network as long as an attacker gets the packet setup correctly. This includes the authentication process for all (including hidden) access levels and the changing of settings in accordance with the gained access rights. Furthermore, because the SMAdata2+ communication channel is unencrypted, an attacker capable of understanding the protocol can eavesdrop on communications. NOTE: the vendor's position is that authentication with encryption is not required on an isolated subnetwork. Also, only Sunny Boy TLST-21 and TL-21 and Sunny Tripower TL-10 and TL-30 could potentially be affected

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.12%	0.69%	+0.57%
2	2025-03-30	0.17%	0.12%	-0.05%
3	2025-03-29	—	0.17%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.12%

0.69%

+0.57%

2025-03-30

0.17%

0.12%

-0.05%

2025-03-29

—

0.17%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
8.1	3.0	HIGH	`CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. 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.	2.2	5.9	[email protected]
4.3	2.0	MEDIUM	`AV:N/AC:M/Au:N/C:P/I:N/A:N` Click to expand Access vector (AV:N) Can be exploited remotely over network reachability. Access complexity (AC:M) Exploitation needs some favorable conditions, but not exceptional ones. Authentication (AU:N) No authentication is required. Confidentiality impact (C:P) Partial confidentiality impact. Integrity impact (I:N) No integrity impact. Availability impact (A:N) No availability impact.	8.6	2.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

8.1

3.0

HIGH

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N): No account or special rights needed—anonymous or random user is enough.
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.

2.2

5.9

[email protected]

4.3

2.0

MEDIUM

AV:N/AC:M/Au:N/C:P/I:N/A:N Click to expand

Access vector (AV:N): Can be exploited remotely over network reachability.
Access complexity (AC:M): Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N): No authentication is required.
Confidentiality impact (C:P): Partial confidentiality impact.
Integrity impact (I:N): No integrity impact.
Availability impact (A:N): No availability impact.

8.6

2.9

[email protected]

Affected software / configurations for CVE-2017-9857

References for CVE-2017-9857

URL	Tags
http://www.sma.de/en/statement-on-cyber-security.html
http://www.sma.de/fileadmin/content/global/specials/documents/cyber-security/Whitepaper-Cyber-Security-AEN1732_07.pdf
https://horusscenario.com/CVE-information/	Third Party Advisory

URL

CVE-2017-9857

Exploit prediction scoring system (EPSS) score for CVE-2017-9857

Common vulnerability scoring system (CVSS) metrics for CVE-2017-9857

Weakness enumeration for CVE-2017-9857

Affected software / configurations for CVE-2017-9857

References for CVE-2017-9857

Vendor	Product	Version	Raw CPE
sma	sunny_boy_3600_firmware	—	cpe:2.3:o:sma:sunny_boy_3600_firmware:-:::::::*
sma	sunny_boy_5000_firmware	—	cpe:2.3:o:sma:sunny_boy_5000_firmware:-:::::::*
sma	sunny_tripower_core1_firmware	—	cpe:2.3:o:sma:sunny_tripower_core1_firmware:-:::::::*
sma	sunny_tripower_15000tl_firmware	—	cpe:2.3:o:sma:sunny_tripower_15000tl_firmware:-:::::::*
sma	sunny_tripower_20000tl_firmware	—	cpe:2.3:o:sma:sunny_tripower_20000tl_firmware:-:::::::*
sma	sunny_tripower_25000tl_firmware	—	cpe:2.3:o:sma:sunny_tripower_25000tl_firmware:-:::::::*
sma	sunny_tripower_5000tl_firmware	—	cpe:2.3:o:sma:sunny_tripower_5000tl_firmware:-:::::::*
sma	sunny_tripower_12000tl_firmware	—	cpe:2.3:o:sma:sunny_tripower_12000tl_firmware:-:::::::*
sma	sunny_tripower_60_firmware	—	cpe:2.3:o:sma:sunny_tripower_60_firmware:-:::::::*
sma	sunny_boy_3000tl_firmware	—	cpe:2.3:o:sma:sunny_boy_3000tl_firmware:-:::::::*
sma	sunny_boy_3600tl_firmware	—	cpe:2.3:o:sma:sunny_boy_3600tl_firmware:-:::::::*
sma	sunny_boy_4000tl_firmware	—	cpe:2.3:o:sma:sunny_boy_4000tl_firmware:-:::::::*
sma	sunny_boy_5000tl_firmware	—	cpe:2.3:o:sma:sunny_boy_5000tl_firmware:-:::::::*
sma	sunny_boy_1.5_firmware	—	cpe:2.3:o:sma:sunny_boy_1.5_firmware:-:::::::*
sma	sunny_boy_2.5_firmware	—	cpe:2.3:o:sma:sunny_boy_2.5_firmware:-:::::::*
sma	sunny_boy_3.0_firmware	—	cpe:2.3:o:sma:sunny_boy_3.0_firmware:-:::::::*
sma	sunny_boy_3.6_firmware	—	cpe:2.3:o:sma:sunny_boy_3.6_firmware:-:::::::*
sma	sunny_boy_4.0_firmware	—	cpe:2.3:o:sma:sunny_boy_4.0_firmware:-:::::::*
sma	sunny_boy_5.0_firmware	—	cpe:2.3:o:sma:sunny_boy_5.0_firmware:-:::::::*
sma	sunny_central_2200_firmware	—	cpe:2.3:o:sma:sunny_central_2200_firmware:-:::::::*
sma	sunny_central_1000cp_xt_firmware	—	cpe:2.3:o:sma:sunny_central_1000cp_xt_firmware:-:::::::*
sma	sunny_central_800cp_xt_firmware	—	cpe:2.3:o:sma:sunny_central_800cp_xt_firmware:-:::::::*
sma	sunny_central_850cp_xt_firmware	—	cpe:2.3:o:sma:sunny_central_850cp_xt_firmware:-:::::::*
sma	sunny_central_900cp_xt_firmware	—	cpe:2.3:o:sma:sunny_central_900cp_xt_firmware:-:::::::*
sma	sunny_central_500cp_xt_firmware	—	cpe:2.3:o:sma:sunny_central_500cp_xt_firmware:-:::::::*
sma	sunny_central_630cp_xt_firmware	—	cpe:2.3:o:sma:sunny_central_630cp_xt_firmware:-:::::::*
sma	sunny_central_720cp_xt_firmware	—	cpe:2.3:o:sma:sunny_central_720cp_xt_firmware:-:::::::*
sma	sunny_central_760cp_xt_firmware	—	cpe:2.3:o:sma:sunny_central_760cp_xt_firmware:-:::::::*
sma	sunny_central_storage_500_firmware	—	cpe:2.3:o:sma:sunny_central_storage_500_firmware:-:::::::*
sma	sunny_central_storage_630_firmware	—	cpe:2.3:o:sma:sunny_central_storage_630_firmware:-:::::::*
sma	sunny_central_storage_720_firmware	—	cpe:2.3:o:sma:sunny_central_storage_720_firmware:-:::::::*
sma	sunny_central_storage_760_firmware	—	cpe:2.3:o:sma:sunny_central_storage_760_firmware:-:::::::*
sma	sunny_central_storage_800_firmware	—	cpe:2.3:o:sma:sunny_central_storage_800_firmware:-:::::::*
sma	sunny_central_storage_850_firmware	—	cpe:2.3:o:sma:sunny_central_storage_850_firmware:-:::::::*
sma	sunny_central_storage_900_firmware	—	cpe:2.3:o:sma:sunny_central_storage_900_firmware:-:::::::*
sma	sunny_central_storage_1000_firmware	—	cpe:2.3:o:sma:sunny_central_storage_1000_firmware:-:::::::*
sma	sunny_central_storage_2200_firmware	—	cpe:2.3:o:sma:sunny_central_storage_2200_firmware:-:::::::*
sma	sunny_central_storage_2500-ev_firmware	—	cpe:2.3:o:sma:sunny_central_storage_2500-ev_firmware:-:::::::*
sma	sunny_boy_storage_2.5_firmware	—	cpe:2.3:o:sma:sunny_boy_storage_2.5_firmware:-:::::::*