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Fencer Intel
medium 6.3

CVE-2021-4242 json

Sapido BR270n/BRC76n/GR297/RB1732 syscmd.htm os command injection

published 3y ago modified 4mo ago also EUVD-2021-34093

cvss
6.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
3.2%
EPSS 3.2% chance of exploitation in 30 days, percentile 88%
public exploits
0
none known

Summary

A vulnerability was found in Sapido BR270n, BRC76n, GR297 and RB1732 and classified as critical. Affected by this issue is some unknown functionality of the file ip/syscmd.htm. The manipulation leads to os command injection. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-214592.

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
last yr.

Exploit prediction

3.15% chance of exploitation in the next 30 days, higher than 88% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • blog.csdn.net https://blog.csdn.net/qq_44159028/article/details/114590267 referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/smallpiggy/Sapido--rce/blob/main/Sapido%E8%B7%AF%E7%94%B1%E5%99%A8-rce.py referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 6.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
NVD 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Sapido BR270n
  • Sapido BRC76n
  • Sapido GR297
  • Sapido RB1732

Classification

Weakness
  • CWE-707 Improper Neutralization
  • CWE-78 Improper Neutralization of Special Elements used in an OS Command

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.