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Fencer Intel
critical 9.8

CVE-2021-33527 json

OS Command Injection in mbDIALUP <= 3.9R0.0

published 5y ago modified 4mo ago also EUVD-2021-20219

cvss
9.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
4.5%
EPSS 4.5% chance of exploitation in 30 days, percentile 91%
public exploits
0
none known

Summary

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.

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Exploit prediction

4.52% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 10.0 AV:N/AC:L/Au:N/C:C/I:C/A:C

Affected products

  • MB connect line mbDIALUP

Classification

Weakness
  • CWE-20 Improper Input Validation

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.