# CVE-2021-20090

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.

- Page: https://www.vulneraibility.com/cve/CVE-2021-20090
- CVSS: 9.8
- Known exploited: yes, in CISA KEV since 2021-11-03; CISA due date 2021-11-17
- EPSS: 99.98% (percentile 100.0)
- Detection templates only, no public exploit found: 1 Nuclei template
- CISA SSVC: exploitation active, automatable yes, technical impact total (assessed 2025-02-06)
- Weakness: CWE-22
- Published: 2021-04-29

## Affected versions

- Buffalo WSR-2533DHPL2, Buffalo WSR-2533DHP3: affected <= 1.24

A version outside these ranges is not a statement that it is unaffected.

## References

- [other] https://www.tenable.com/security/research/tra-2021-13
- [advisory] https://www.kb.cert.org/vuls/id/914124
- [other] https://www.secpod.com/blog/arcadyan-based-routers-and-modems-under-active-exploitation/
- [other] https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20090

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.