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Fencer Intel
high 8.8

CVE-2020-5756 json

Grandstream GWN7000 firmware version 1.0.9.4 and below allows authenticated remote users to modify the system's crontab via undocumented AP…

published 6y ago modified 4mo ago also EUVD-2020-26915

cvss
8.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.5%
EPSS 2.5% chance of exploitation in 30 days, percentile 84%
public exploits
0
none known

Summary

Grandstream GWN7000 firmware version 1.0.9.4 and below allows authenticated remote users to modify the system's crontab via undocumented API. An attacker can use this functionality to execute arbitrary OS commands on the router.

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Exploit prediction

2.47% chance of exploitation in the next 30 days, higher than 84% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • tenable.com https://www.tenable.com/cve/CVE-2020-5756 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 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

  • Tenable Grandstream GWN7000

Classification

Weakness
  • CWE-489 Active Debug Code
  • 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.