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Vulnerabilities

Vulnerability · CVE-2021-20091

Buffalo WSR-2533DHPL2 firmware version <= 1.02 and WSR-2533DHP3 firmware version <= 1.24 Configuration Injection

Published Sep 20, 2021 · catalog updated Sep 20, 2021 · Buffalo WSR-2533DHPL2 firmware version

Patch now

CVE-2021-20091 is in the CISA known-exploited catalog. Confirm Buffalo WSR-2533DHPL2 firmware version against the vendor advisory and apply that fix. The CVSS score does not change the priority.

Gaps on this record

  • The stored product name is a package slug. The name on this page is taken from the title (Buffalo WSR-2533DHPL2 firmware version).
  • No version range is stored. A customer cannot check an installed version against this record.
Severity
Unknown—
Known exploitation
CISA KEV and VulnCheck KEV
EPSS
8.46%
Remediation
Remediation guidance
Affected products
vendor buffalo wsr-2533dhpl2-bk_firmware

The web interfaces of Buffalo WSR-2533DHPL2 firmware version <= 1.02 and WSR-2533DHP3 firmware version <= 1.24 do not properly sanitize user input. An authenticated remote attacker could leverage this vulnerability to alter device configuration, potentially gaining remote code execution.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • vendor buffalo wsr-2533dhpl2-bk_firmwareversion unspecified

How to fix CVE-2021-20091

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

CVE-2021-20091 is in the CISA known-exploited catalog. Confirm Buffalo WSR-2533DHPL2 firmware version against the vendor advisory and apply that fix. The CVSS score does not change the priority.

Which versions are affected?

Affected version ranges are not on this record. Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

What should an analyst verify?

No weakness class is stored. EPSS 8.46%. The CISA KEV listing is the exploitation evidence. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Sep 20, 2021 · VulnCheck KEV

    Detected

    The web interfaces of Buffalo WSR-2533DHPL2 firmware version <= 1.02 and WSR-2533DHP3 firmware version <= 1.24 do not properly sanitize user input. An authenticated remote attacker could leverage this vulnerability to alter device configuration, potentially gaining remote code execution.

  2. Sep 20, 2021 · CISA KEV

    Known exploited

    Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

Sources

  • CVE.orgVulnerability recordCVE-2021-20091

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2021-20091

    30-day exploitation probability 8.5%

    first.org
  • VulnCheck KEVConfirmed exploitationCVE-2021-20091

    The web interfaces of Buffalo WSR-2533DHPL2 firmware version <= 1.02 and WSR-2533DHP3 firmware version <= 1.24 do not properly sanitize user input. An authenticated remote attacker could leverage this vulnerability to alter device configuration, potentially gaining remote code ex

    vulncheck.com

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.