CVE-2021-34543

Exp

The web administration server in Solar-Log 500 before 2.8.2 Build 52 does not require authentication, which allows remote attackers to gain administrative privileges by connecting to the server. As a result, the attacker can modify configuration files and change the system status. Fixed with 3.0.0-60 11.10.2013 for SL 200, 500, 1000 / not existing for SL 250, 300, 1200, 2000, SL 50 Gateway, SL Base.

Published: 2021-12-07 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-34543 is rated High Exploit Risk (76.4/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.88%). 2 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +1.69% over the last day, indicating growing attacker interest. Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2021-34543

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-34543

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 2026-06-15 1.19% 2.88% +1.69%
2 2025-03-30 1.75% 1.19% -0.56%
3 2025-03-29 — 1.75% —

Full EPSS history (30 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-34543

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N 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:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:P/A:N 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:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2021-34543

Affected software / configurations for CVE-2021-34543

Vendor Product Version Raw CPE
bkw solar-log_500_firmware <= 2.8.1 cpe:2.3:o:bkw:solar-log_500_firmware:*:*:*:*:*:*:*:*
bkw solar-log_500_firmware 2.8.2 cpe:2.3:o:bkw:solar-log_500_firmware:2.8.2:build_50:*:*:*:*:*:*

References for CVE-2021-34543

URL Tags
https://drive.google.com/file/d/1z1TaANlDyX4SOP2vjNzkPQI3nETL9kZM/view?usp=sharing Exploit Third Party Advisory
https://www.exploit-db.com/exploits/49986 Exploit Third Party Advisory VDB Entry
https://www.solar-log.com/en/support/firmware/ Product Release Notes Vendor Advisory
cvelogic Threat Intelligence