CVE-2021-20090 KEV
9.8
CRITICAL · CVSS 3.1 · EPSS 100% (pctl 100)
Patch first
On CISA KEV — known exploited in the wild, due 2021-11-17.
Description
A path traversal vulnerability in the web interfaces of Buffalo WSR-2533DHPL2 firmware version <= 1.02 and WSR-2533DHP3 firmware version <= 1.24 could allow unauthenticated remote attackers to bypass authentication.
Scoring
| CVSS | 9.8 (CRITICAL, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 99.98% — more likely to be exploited than 100% of all CVEs |
| Weakness | CWE-22 |
| On CISA KEV | yes — remediate by 2021-11-17 |
| Public exploit | none known |
| Published | 2021-04-29 |
| Last modified | 2026-06-17 |
CISA KEV
| Name | Arcadyan Buffalo Firmware Path Traversal Vulnerability |
|---|---|
| Added | 2021-11-03 |
| Due | 2021-11-17 |
| Vendor / product | Arcadyan / Buffalo Firmware |
| Ransomware use | none reported |
Affected (4)
| Vendor | Product |
|---|---|
| buffalo | wsr-2533dhp3-bk |
| buffalo | wsr-2533dhp3-bk firmware |
| buffalo | wsr-2533dhpl2-bk |
| buffalo | wsr-2533dhpl2-bk firmware |
References
- https://www.kb.cert.org/vuls/id/914124
- https://www.secpod.com/blog/arcadyan-based-routers-and-modems-under-active-exploitation/
- https://www.tenable.com/security/research/tra-2021-13
- https://www.kb.cert.org/vuls/id/914124
- https://www.secpod.com/blog/arcadyan-based-routers-and-modems-under-active-exploitation/
- https://www.tenable.com/security/research/tra-2021-13
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20090
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