Unauthenticated DoS in SolarWinds Serv-U via deflate POST requests
CVE-2026-28318 is an uncontrolled resource consumption vulnerability in SolarWinds Serv-U affecting versions prior to 15.5.4 Hotfix 1. According to the provided content, the flaw can be triggered remotely without authentication by sending specially crafted HTTP POST requests that include the header "Content-Encoding: deflate," causing the Serv-U service to crash. The issue affects SolarWinds Serv-U on Windows and Linux and results in an unauthenticated denial-of-service condition rather than code execution.
Are you exposed to this one?
Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.
Impact, mitigation & remediation
What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.
Impact
What an attacker gets, and what they’ve been doing with it.
Mitigation
If you can’t patch tonight, do this now.
Remediation
Patch, then assume compromise.
Exploits
No public exploits tracked yet. Mallory keeps watching.
No public exploit code observed for this vulnerability.
Affected products & vendors
Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.
Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.
Recent activity
15 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
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.
The version that knows your environment.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.