Summary
The UTF8DataInputJsonParser, which is used when parsing from a java.io.DataInput source, bypasses the maxNestingDepth constraint (default: 500) defined in StreamReadConstraints.
A similar issue was found in ReaderBasedJsonParser.
This allows a user to supply a JSON document with excessive nesting, which can cause a StackOverflowError when the structure is processed, leading to a Denial of Service (DoS).
The related fix for com.fasterxml.jackson.core:jackson-core, CVE-2025-52999, was not fully applied to tools.jackson.core:jackson-core until the 3.1.0 release. It is recommended that 3.0.x users upgrade.
Workarounds
Users should avoid parsing input files from untrusted sources.
Resources
GHSA-6v53-7c9g-w56r
https://nvd.nist.gov/vuln/detail/CVE-2025-52999
https://github.com/FasterXML/jackson-core/pull/1554
Impact
The application allocates resources such as memory, threads, or file descriptors based on untrusted input without enforcing a cap. Typical impact: resource exhaustion leading to denial of service.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
jackson-core contains a configurable limit for how deep Jackson will traverse in an input document. This check was missing in a few places in tools.jackson.core:jackson-core.
The change is in https://github.com/FasterXML/jackson-core/pull/1554. jackson-core will throw a StreamConstraintsException if the limit is reached.
jackson-databind also benefits from this change because it uses jackson-core to parse JSON inputs.
Frequently Asked Questions
- What is CVE-2026-29062? CVE-2026-29062 is a high-severity allocation of resources without limits or throttling vulnerability in tools.jackson.core:jackson-core (maven), affecting versions >= 3.0.0, < 3.1.0. It is fixed in 3.1.0. The application allocates resources such as memory, threads, or file descriptors based on untrusted input without enforcing a cap.
- Which versions of tools.jackson.core:jackson-core are affected by CVE-2026-29062? tools.jackson.core:jackson-core (maven) versions >= 3.0.0, < 3.1.0 is affected.
- Is there a fix for CVE-2026-29062? Yes. CVE-2026-29062 is fixed in 3.1.0. Upgrade to this version or later.
- Is CVE-2026-29062 exploitable, and should I be worried? Whether CVE-2026-29062 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-29062 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-29062? Upgrade
tools.jackson.core:jackson-coreto 3.1.0 or later.