u/SpotlessCheetah

August 2026's patch Tuesday fixes a vulnerability in TFTP server remote code execution, CVE-2026-62893.

• ref: https://www.sentinelone.com/vulnerability-database/cve-2026-62893/

Affected service: WDS

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62893

Post installation of KB5121650 addresses this vulnerability.

If you find yourself able to PXE boot, but get boot up errors, check your MDT server and open up server manager. Go to WDS and under Events, search for 4101 - "the following client failed TFTP download..."

If you that error, open up the WDS application.

• Expand Servers > right click on your mdt fqdn instance > properties > TFTP
• and uncheck "Enable Variable Window Extension"
• Restart your WDS services and try to PXE boot again.

August 2026's patch Tuesday fixes a vulnerability in TFTP server remote code execution, CVE-2026-62893.

• ref: https://www.sentinelone.com/vulnerability-database/cve-2026-62893/

Affected service: WDS

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62893

Post installation of KB5121650 addresses this vulnerability.

If you find yourself able to PXE boot, but get boot up errors, check your MDT server and open up server manager. Go to WDS and under Events, search for 4101 - "the following client failed TFTP download..."

If you that error, open up the WDS application.

• Expand Servers > right click on your mdt fqdn instance > properties > TFTP
• and uncheck "Enable Variable Window Extension"
• Restart your WDS services and try to PXE boot again.