CVE-2021-40859

CVE-2021-40859 is a critical-severity vulnerability in Auerswald Compact 5500r Firmware with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 72% places it in the 99th percentile, indicating an elevated likelihood of exploitation.

Key facts

Description

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.

Frequently asked questions

What is CVE-2021-40859?
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.
How severe is CVE-2021-40859?
CVE-2021-40859 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-40859 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 72% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-40859?
CVE-2021-40859 primarily affects Auerswald Compact 5500r Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-40859?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-40859 published?
CVE-2021-40859 was published on 2021-12-07 and last updated on 2026-06-17.

References

Affected products (2)