Unauthenticated DoS in SolarWinds Serv-U via deflate POST requests
CVE-2026-28318 is an unauthenticated denial-of-service vulnerability in SolarWinds Serv-U affecting versions prior to 15.5.4 Hotfix 1. According to the provided content, the flaw is caused by uncontrolled resource consumption and can be triggered by specially crafted HTTP POST requests that use the header "Content-Encoding: deflate." Successful exploitation causes the Serv-U service to crash. The issue affects SolarWinds Serv-U managed file transfer / FTP server software on supported platforms, including Windows and Linux.
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Recent activity
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A high-severity denial-of-service vulnerability in SolarWinds Serv-U file transfer software that can be exploited via low-complexity, unauthenticated POST requests to crash the Serv-U service.
A high-severity denial-of-service vulnerability in SolarWinds Serv-U caused by uncontrolled resource consumption, exploitable via specially crafted unauthenticated POST requests using Content-Encoding: deflate to crash the Serv-U service.
An unauthenticated denial-of-service vulnerability affecting SolarWinds Serv-U in versions prior to 15.5.4 HF1.
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Cross-references every affected SKU, including bundled OEM variants.
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