How severe is CVE-2021-34543?

CVE-2021-34543 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2021-34543 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34543?

CVE-2021-34543 primarily affects Bkw Solar-log 500 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-34543?

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-2021-34543 published?

CVE-2021-34543 was published on 2021-12-07 and last updated on 2026-06-17.

CVE-2021-34543

CVE-2021-34543 is a high-severity vulnerability in Bkw Solar-log 500 Firmware with a CVSS 3.x base score of 7.5. 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-306.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Bkw Solar-log 500 Firmware
Published: 2021-12-07
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2021-34543?: 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.
How severe is CVE-2021-34543?: CVE-2021-34543 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2021-34543 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34543?: CVE-2021-34543 primarily affects Bkw Solar-log 500 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-34543?: 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-2021-34543 published?: CVE-2021-34543 was published on 2021-12-07 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:bkw:solar-log_500_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:bkw:solar-log_500_firmware:2.8.2:build_50:*:*:*:*:*:*

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