CVE-2021-33527
CVE-2021-33527 is a critical-severity vulnerability in Mbconnectline Mbdialup with a CVSS 3.x base score of 9.8. 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-20.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 10.0
- EPSS exploit prediction: 5% (90th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Mbconnectline Mbdialup
- Published:
- Last modified:
Description
In MB connect line mbDIALUP versions <= 3.9R0.0 a remote attacker can send a specifically crafted HTTP request to the service running with NT AUTHORITY\SYSTEM that will not correctly validate the input. This can lead to an arbitrary code execution with the privileges of the service.
Frequently asked questions
- What is CVE-2021-33527?
- In MB connect line mbDIALUP versions <= 3.9R0.0 a remote attacker can send a specifically crafted HTTP request to the service running with NT AUTHORITY\SYSTEM that will not correctly validate the input. This can lead to an arbitrary code execution with the privileges of the service.
- How severe is CVE-2021-33527?
- CVE-2021-33527 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-33527 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-33527?
- CVE-2021-33527 affects Mbconnectline Mbdialup. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-33527?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-33527 published?
- CVE-2021-33527 was published on 2021-08-02 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:mbconnectline:mbdialup:*:*:*:*:*:*:*:*
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