How severe is CVE-2021-34575?

CVE-2021-34575 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 high, integrity none, and availability none.

Is CVE-2021-34575 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34575?

CVE-2021-34575 primarily affects Mbconnectline Mbconnect24. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-34575?

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-2021-34575 published?

CVE-2021-34575 was published on 2021-08-02 and last updated on 2026-06-17.

CVE-2021-34575

CVE-2021-34575 is a high-severity vulnerability in Mbconnectline Mbconnect24 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-203.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Mbconnectline Mbconnect24
Published: 2021-08-02
Last modified: 2026-06-17

Description

In MB connect line mymbCONNECT24, mbCONNECT24 in versions <= 2.8.0 an unauthenticated user can enumerate valid users by checking what kind of response the server sends.

Frequently asked questions

What is CVE-2021-34575?: In MB connect line mymbCONNECT24, mbCONNECT24 in versions <= 2.8.0 an unauthenticated user can enumerate valid users by checking what kind of response the server sends.
How severe is CVE-2021-34575?: CVE-2021-34575 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 high, integrity none, and availability none.
Is CVE-2021-34575 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34575?: CVE-2021-34575 primarily affects Mbconnectline Mbconnect24. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-34575?: 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-2021-34575 published?: CVE-2021-34575 was published on 2021-08-02 and last updated on 2026-06-17.

References

https://cert.vde.com/de-de/advisories/vde-2021-030

Affected products (2)

cpe:2.3:a:mbconnectline:mbconnect24:*:*:*:*:*:*:*:*
cpe:2.3:a:mbconnectline:mymbconnect24:*:*:*:*:*:*:*:*

More vulnerabilities in Mbconnectline Mbconnect24

CVE-2020-35565 — Critical (CVSS 9.8): An issue was discovered in MB CONNECT LINE mymbCONNECT24 and mbCONNECT24 through 2.6.2. The login pages bruteforce…
CVE-2020-10383 — Critical (CVSS 9.8): An issue was discovered in the MB CONNECT LINE mymbCONNECT24 and mbCONNECT24 software in all versions through 2.5.0.…
CVE-2026-33615 — Critical (CVSS 9.1): An unauthenticated remote attacker can exploit an unauthenticated SQL Injection vulnerability in the setinfo endpoint…
CVE-2023-0985 — High (CVSS 8.8): An Authorization Bypass vulnerability was found in MB Connect Lines mbCONNECT24, mymbCONNECT24 and Helmholz' myREX24…
CVE-2020-10382 — High (CVSS 8.8): An issue was discovered in the MB CONNECT LINE mymbCONNECT24 and mbCONNECT24 software in all versions through 2.5.0.…
CVE-2024-45273 — High (CVSS 8.4): An unauthenticated local attacker can decrypt the devices config file and therefore compromise the device due to a weak…

All CVEs affecting Mbconnectline Mbconnect24 →

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