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Fencer Intel
high 8.8

CVE-2021-42839 json

Grand Vice info Co. webopac7 - Arbitrary File Upload

published 4y ago modified 4mo ago also EUVD-2021-29794

cvss
8.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
2.4%
EPSS 2.4% chance of exploitation in 30 days, percentile 84%
public exploits
0
none known

Summary

Grand Vice info Co. webopac7 file upload function fails to filter special characters. While logging in with general user’s permission, remote attackers can upload malicious script and execute arbitrary code to control the system or interrupt services.

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Exploit prediction

2.43% chance of exploitation in the next 30 days, higher than 84% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 9.0 AV:N/AC:L/Au:S/C:C/I:C/A:C

Affected products

  • Grand Vice info Co. webopac7

Classification

Weakness
  • CWE-434 Unrestricted Upload of File with Dangerous Type

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.