CVE-2021-28150
MediumExploitedHongdian H8922 3.0.5 devices allow the unprivileged guest user to read cli.conf (with the administrator password and other sensitive data) via /backup2.cgi.
Published May 6, 2021 · Updated Nov 21, 2024
Key Facts
Patch immediately- CVE-2021-28150 is a medium-severity vulnerability (CVSS 5.5 v3.1) affecting H8922 Firmware (Hongdian).
- It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since May 6, 2021. No public exploit code is known.
- EPSS estimates a 2.8% probability of exploitation in the next 30 days.
- No fixed version is listed yet; check the vendor advisory for mitigations.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS (30-day exploit likelihood)
2.8%
Higher than 86.2% of all scored CVEs
Exploited in the wild
Yes
2 catalog listings
Public exploit code
None known
Get the full CVE-2021-28150 brief as a PDF
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Description
Hongdian H8922 3.0.5 devices allow the unprivileged guest user to read cli.conf (with the administrator password and other sensitive data) via /backup2.cgi.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Aug 23, 2025 | n/a | Not reported |
| CIRCL KEV | May 6, 2021 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
1 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| H8922 FirmwareHongdian | 3.0.5 | n/a |
Timeline
Publicly disclosed
May 6, 2021
Added to CIRCL KEV
May 6, 2021
Last updated
Nov 21, 2024
Added to Industry KEV feed
Aug 23, 2025
Weakness Type
- CWE-425 Direct Request ('Forced Browsing')
References
- advisoryhttp://en.hongdian.com/Products/Details/H8922
- exploitVulnCheck exploitation report
- exploitVulnCheck exploitation report
- exploitVulnCheck exploitation report
- exploitVulnCheck exploitation report
FAQ
Common Questions.
Hongdian H8922 3.0.5 devices allow the unprivileged guest user to read cli.conf (with the administrator password and other sensitive data) via /backup2.cgi.
Affected: H8922 Firmware (Hongdian) versions 3.0.5. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed, CIRCL KEV since May 6, 2021.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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