Executive brief
FasterXML jackson-core is a widely used Java library for processing JSON data. A vulnerability in certain versions allows an attacker to crash an application by sending a specially crafted JSON file with deeply nested structures. This can lead to a denial-of-service (DoS) condition, making the affected service unavailable to legitimate users.
Technical details
A vulnerability exists in jackson-core versions 3.0.0 through 3.0.x where the UTF8DataInputJsonParser and ReaderBasedJsonParser components bypass the 'maxNestingDepth' constraint (default 500) defined in StreamReadConstraints. By providing a JSON document with excessive nesting, a remote, unauthenticated attacker can trigger a StackOverflowError during processing. This leads to a Denial of Service (DoS) by crashing the JVM thread or the entire application. The issue is a regression or incomplete application of previous fixes (like CVE-2025-52999) to the 3.x branch. The vulnerability is addressed in version 3.1.0.
Affected products
- FasterXML jackson-core >= 3.0.0, < 3.1.0
Timeline
- 2026-02-19: patched: Fix merged into 3.x branch via pull request 1554.
- 2026-03-03: advisory: GitHub Security Advisory GHSA-6v53-7c9g-w56r published.
- 2026-03-06: disclosed: CVE-2026-29062 published to NVD.
References
- https://github.com/FasterXML/jackson-core/commit/8b25fd67f20583e75fb09564ce1eaab06cd5a902
- https://github.com/FasterXML/jackson-core/pull/1554
- https://github.com/FasterXML/jackson-core/security/advisories/GHSA-6v53-7c9g-w56r
- https://access.redhat.com/security/cve/CVE-2026-29062
- https://bugzilla.redhat.com/show_bug.cgi?id=2445135
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-29062.json