CVE-2026-33012 Micronaut Framework vulnerable to a Denial of Service in HTML error response caching
Remote attackers can cause denial of service via unbounded heap growth in Micronaut Framework's HTML error response caching mechanism.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-33012?
CVE-2026-33012 is a high-severity denial of service vulnerability in micronaut-projects micronaut-core, published on 20 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Micronaut Framework is a JVM-based full stack Java framework designed for building modular, easily testable JVM applications. Versions 4.7.0 through 4.10.16 used an unbounded ConcurrentHashMap cache with no eviction policy in its DefaultHtmlErrorResponseBodyProvider. If the application throws an exception whose message may be influenced by an attacker, (for example, including request query value parameters) it could be used by remote attackers to cause an unbounded heap growth and OutOfMemoryError, leading to DoS. This issue has been fixed in version 4.10.7.
Weakness: CWE-770
Which versions are affected by CVE-2026-33012?
2 open source packages ship an affected version, including io.micronaut:micronaut-http-server. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
io.micronaut:micronaut-http-server Maven | From 4.7.0 | 4.10.17 |
io.micronaut:micronaut-http-server Maven | From 4.7.0 | 4.10.17 |
Products include Objectcomputing Micronaut.
How do I fix CVE-2026-33012?
Upgrade io.micronaut:micronaut-http-server to 4.10.17 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-33012 being exploited?
There is no known exploitation of CVE-2026-33012 in the wild and no public exploit code.
Other vulnerabilities in micronaut-projects micronaut-core
- CVE-2020-7611 Micronaut's HTTP client is vulnerable to HTTP Request Header Injection
- CVE-2026-33013 Micronaut vulnerable to DoS via crafted form-urlencoded body binding with descending array indices
- CVE-2021-32769 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in micronaut-core
- CVE-2022-21700 Memory leak in micronaut-core
- CVE-2024-23639 micronaut-core management endpoints vulnerable to drive-by localhost attack
Sources
Also known as GHSA-2hcp-gjrf-7fhc, MINI-wmvw-6pwf-gvh6.