CVE-2023-45742 is a high severity integer overflow in the boa web server of the Realtek rtl819x Jungle SDK v3.4.11, scored 7.2. A series of HTTP requests can lead to code execution. Realtek released a fix on 2024-05-20, but the LevelOne WBR-6013 router has none.
What's affected
The NVD record lists the Realtek rtl819x Jungle SDK v3.4.11 and the LevelOne WBR-6013 router, firmware RER4_A_v3411b_2T2R_LEV_09_170623. Cisco Talos, in report TALOS-2023-1877, lists the same two.
Talos gives the patch status. Realtek released a fix on 2024-05-20 and has provided updated software to its customers. LevelOne, which makes the WBR-6013, has declined to patch. The report does not name a fixed SDK version, so ask Realtek or your device vendor which build contains the fix.
The score is 7.2, High, with the vector CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. The record and Talos agree. It needs an administrative login on the device.
How to check if you're exposed
If you build products on the Realtek SDK, look at your SDK version and at the boa web server code in your tree. If you operate LevelOne WBR-6013 routers, the firmware version is on the device's status page, and the affected build string is RER4_A_v3411b_2T2R_LEV_09_170623.
Check where the router's management interface is reachable. The attack needs administrator access, so exposure to the internet or to untrusted users makes the difference between a theoretical and a practical risk.
What to do now
- Find any Realtek rtl819x based products you build or operate.
- For products you build, get the updated SDK from Realtek and rebuild.
- For LevelOne WBR-6013 routers, plan replacement, since the vendor has declined to patch.
- Turn off remote management and restrict the admin interface to a trusted internal range.
- Change default administrator credentials on every such device.
Why it matters
The weakness is an integer overflow, CWE-190. A calculation, in this case in the code that updates configuration into flash, produces a number too large for its type. The wrapped value is then used to size or index memory, which can lead to memory corruption and code execution. The record says the device may be exploited with a sequence of requests.
This one shows the supply chain shape of embedded bugs. The flaw lives in an SDK, ships in many products, and is fixed by the chip vendor, but each device maker has to pick up and release the fix. Some do not, as the Talos report notes for LevelOne.
The CVE is not on the CISA Known Exploited Vulnerabilities list, and Talos does not report exploitation.
Safeguard's free in-browser dependency scan at gold.safeguard.sh/scan reads the manifests and lockfiles of software projects. It will not see firmware or device images, so for this issue the asset inventory and the vendor advisory are your main tools.
Try it yourself
Click through it at your own pace, or open it full screen.
Quick check
Does Realtek have a fix?
Yes. Talos reports a Realtek fix on 2024-05-20, supplied to customers.
What about the WBR-6013?
Talos says LevelOne declined to patch, so replacement is the safer plan.
Sources
Last reviewed: 19 October 2026.
