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Fencer Intel
critical 9.8

CVE-2021-40859 in the critical feed json

Backdoors were discovered in Auerswald COMpact 5500R 7.8A and 8.0B devices, that allow attackers with access to the web based management ap…

published 4y ago modified 4mo ago also EUVD-2021-28015

cvss
9.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
72.0%
EPSS 72.0% chance of exploitation in 30 days, percentile 99.4%
public exploits
1
Exploit-DB, plus a Nuclei check

Summary

Backdoors were discovered in Auerswald COMpact 5500R 7.8A and 8.0B devices, that allow attackers with access to the web based management application full administrative access to the device.

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Timeline

  1. First public exploit (EDB-50569)
  2. Published

Exploit prediction

71.98% chance of exploitation in the next 30 days, higher than 99.4% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • EDB-50569 Auerswald COMpact 8.0B - Multiple Backdoors remote, 2021-12-06
  • Nuclei template Auerswald COMpact 5500R 7.8A and 8.0B Devices Backdoor nuclei detection template
  • redteam-pentesting.de https://www.redteam-pentesting.de/en/advisories/rt-sa-2021-007/-auerswald-compact-multiple-backdoors referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 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

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.