CISA Alerts on Actively Exploited SolarWinds Serv-U Denial-of

Gbhackers •Eswar • June 6, 2026

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has officially added a critical vulnerability in SolarWinds Serv-U to its Known Exploited Vulnerabilities (KEV) catalog. Tracked as CVE-2026-28318, this flaw allows unauthenticated threat actors to remotely crash the file transfer service. With active exploitation observed in the wild, this development signals a severe risk to enterprise […]

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Active Exploitation of SolarWinds Serv-U Flaw CVE-2026-28318 The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has issued a warning regarding the active exploitation of a high-severity vulnerability in SolarWinds Serv-U, tracked as CVE-2026-28318. This flaw allows remote attackers to crash the Serv-U service using specially crafted POST requests without requiring authentication. The vulnerability stems from uncontrolled resource consumption and affects both Windows and Linux versions of Serv-U. SolarWinds released a hotfix (15.5.4 Hotfix 1) on June 4, 2026, to address this issue. CISA has added this CVE to its Known Exploited Vulnerabilities Catalog and mandated that all Federal Civilian Executive Branch agencies patch their servers by June 19, 2026. There are over 12,000 Serv-U servers exposed online, increasing the risk of exploitation. Administrators are advised to limit access to known addresses and block specific POST requests until the patch can be applied. 13 sources 73

Extracted Entities

CVEs (1)

CVE-2026-28318

Platforms (1)

SolarWinds Serv-U