DoS in Micrometer HTTP server instrumentations
CVE-2026-40984 is a high-severity denial-of-service vulnerability in Micrometer HTTP server instrumentations. According to the provided advisory content, specially crafted HTTP requests can trigger a DoS condition in applications using vulnerable versions of io.micrometer:micrometer-core, micrometer-jetty11, or micrometer-jetty12. The issue affects deployments where one or more HTTP server instrumentations from those artifacts are configured and metrics are being recorded through the affected instrumentation. Affected versions are micrometer-core 1.16.0-1.16.5, 1.15.0-1.15.11, 1.14.0-1.14.15, 1.13.0-1.13.18, and 1.9.0-1.9.17; micrometer-jetty11 1.16.0-1.16.5, 1.15.0-1.15.11, 1.14.0-1.14.15, and 1.13.0-1.13.18; and micrometer-jetty12 1.16.0-1.16.5, 1.15.0-1.15.11, 1.14.0-1.14.15, and 1.13.0-1.13.18. The specific vulnerable function is not identified in the provided content.
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.
Recent activity
6 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A denial-of-service vulnerability in Micrometer HTTP server instrumentations affecting Micrometer / Micrometer-core / jetty11 / jetty12 multiple versions.
A denial-of-service vulnerability in Micrometer HTTP server instrumentations that can be triggered by specially crafted HTTP requests when affected Micrometer components are in use and metrics are recorded through the instrumentation.
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.