CVE-2026-29062: jackson-core: Nesting Depth Constraint Bypass in `UTF8DataInputJsonParser` potentially allowing Resource Exhaustion
### 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. ### Patches 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. ### Workarounds Users should avoid parsing input files from untrusted sources. ### Resources [GHSA-6v53-7c9g-w56r](https://github.com/FasterXML/jackson-core/security/advisories/GHSA-6v53-7c9g-w56r) https://nvd.nist.gov/vuln/detail/CVE-2025-52999 https://github.com/FasterXML/jackson-core/pull/1554
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is the severity of CVE-2026-29062?
The severity of CVE-2026-29062 is considered high due to its potential for denial of service attacks through JSON parsing.
How do I fix CVE-2026-29062?
To fix CVE-2026-29062, upgrade to the latest version of the jackson-core package beyond 3.1.0.
What software is affected by CVE-2026-29062?
CVE-2026-29062 affects jackson-core version 3.0.0 through 3.1.0.
What is the impact of CVE-2026-29062?
The impact of CVE-2026-29062 includes bypassing maxNestingDepth constraints, leading to potential denial of service.
Can CVE-2026-29062 be exploited remotely?
Yes, CVE-2026-29062 can be exploited remotely if a malicious JSON document is supplied to the vulnerable parser.