BL-WR9000: Out-of-bounds Read
CVE-2026-4227 is a high-severity out-of-bounds read vulnerability in BL-WR9000 from Lb-link, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected BL-WR9000 versions: 2.4.9. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.76% chance of exploitation within 30 days, higher than 56% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of BL-WR9000 you run against the affected versions below, and install the vendor's latest release.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| LB-LINK | BL-WR9000 | 2.4.9 | Not stated |
| Lb-link | Bl-wr9000 Firmware | 2.4.9 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 7.4 | High | CNA (vuldb.com) |
| CVSS 3.1 | 8.8 | High | CNA (vuldb.com) |
| CVSS 3.1 | 7.5 | High | NVD |
| CVSS 2.0 | 9.0 | High | CNA (vuldb.com) |
Official description
A security vulnerability has been detected in LB-LINK BL-WR9000 2.4.9. The impacted element is the function sub_44D844 of the file /goform/get_hidessid_cfg. The manipulation leads to buffer overflow. It is possible to initiate the attack remotely. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- vuldb.com/?id.351150Third Party Advisory, VDB Entry
- vuldb.com/?submit.771209Third Party Advisory, VDB Entry
Technical write-ups (may include proof of concept)
- github.com/glkfc/IoT-Vulnerability/blob/main/LB-LINK/LB-LINK_HideSSID%20stack%20overflow_EN.mdExploit, Third Party Advisory
Other references
- vuldb.com/?ctiid.351150Permissions Required, VDB Entry
Other vulnerabilities in BL-WR9000
- 9.8 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
Recent Out-of-bounds Read vulnerabilities
- 9.1 Critical severity
- 7.1 High severity
- 7.1 High severity
- 7.7 High severity
- 7.5 High severity
- 7.5 High severity
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