CVE-2022-34840 — Use of hard-coded credentials vulnerability in multiple Buffalo network devices

Use of hard-coded credentials vulnerability in multiple Buffalo network devices allows a network-adjacent attacker to alter?configuration settings of the device. The affected products/versions are as follows: WZR-300HP firmware Ver. 2.00 and earlier, WZR-450HP firmware Ver. 2.00

01What is this vulnerability?

Use of hard-coded credentials vulnerability in multiple Buffalo network devices allows a network-adjacent attacker to alter?configuration settings of the device. The affected products/versions are as follows: WZR-300HP firmware Ver. 2.00 and earlier, WZR-450HP firmware Ver. 2.00 and earlier, WZR-600DHP firmware Ver. 2.00 and earlier, WZR-900DHP firmware Ver. 1.15 and earlier, HW-450HP-ZWE…

02Affected products

Vendor	Product	Versions
BUFFALO INC.	Buffalo network devices	WZR-300HP firmware Ver. 2.00 and earlier, WZR-450HP firmware Ver. 2.00 and earlier, WZR-600DHP firmware Ver. 2.00 and earlier, WZR-900DHP firmware Ver. 1.15 and earlier, HW-450HP-ZWE firmware Ver. 2.00 and earlier, WZR-450HP-CWT firmware Ver. 2.00 and earlier, WZR-450HP-UB firmware Ver. 2.00 and earlier, WZR-600DHP2 firmware Ver. 1.15 and earlier, and WZR-D1100H firmware Ver. 2.00 and earlier.

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2022-12-07T00:00:00.000Z
• Last modified: 2025-04-23T16:10:12.366Z

09References

• www.buffalo.jp — https://www.buffalo.jp/news/detail/20221003-01.html
• jvn.jp — https://jvn.jp/en/vu/JVNVU92805279/index.html