Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Attack requirements (AT:N) | No attack requirements |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Confidentiality (VC:H) | High confidentiality impact |
| Integrity (VI:H) | High integrity impact |
| Availability (VA:H) | High availability impact |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
About Blackbeartechhive Atop Ehg2408 Firmware
CVE-2026-3823 affects Blackbeartechhive Atop Ehg2408 Firmware, a product from Blackbeartechhive. Before acting, confirm where Blackbeartechhive Atop Ehg2408 Firmware runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: EHG2408 series switch developed by Atop Technologies has a Stack-based Buffer Overflow vulnerability, allowing unauthenticated remote attackers to control the program's execution flow and execute arbitrary code.
The weakness class is Stack Buffer Overflow. A write past the end of a stack buffer can corrupt control data.
Based on its CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Blackbeartechhive Atop Ehg2408 Firmware |
| Affected versions | Atop Ehg2408 Firmware before 3.36; Atop Ehg2408-2sfp Firmware before 3.36 |
| Published | Mar 9, 2026 |
| Last modified | Jul 7, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | twcert@cert.org.tw |
How to detect it
- Inventory every instance of Blackbeartechhive Atop Ehg2408 Firmware and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Blackbeartechhive Atop Ehg2408 Firmware named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Blackbeartechhive Atop Ehg2408 Firmware to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-121: Stack Buffer Overflow More CVEs with this weakness
- CWE-787: Out of Bounds Write More CVEs with this weakness
Technical References
Frequently asked questions
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