CVE-2026-68494
Description
A flaw was found in jackson-core. A remote attacker can exploit an incomplete fix in the non-blocking JSON parser by streaming specially crafted JSON data in small chunks. This bypasses the intended number length constraint, causing the parser to accumulate excessive memory per connection. This uncontrolled memory growth can lead to a denial of service (DoS) by exhausting the Java Virtual Machine (JVM) heap.
Statement
This is an Important denial of service vulnerability in jackson-core's asynchronous JSON parser. A remote, unauthenticated attacker can exploit an incomplete fix to bypass number length constraints, leading to unbounded memory accumulation and potential JVM heap exhaustion in reactive frameworks processing chunked JSON input.
Mitigation
Upgrade com.fasterxml.jackson.core:jackson-core to a fixed version, such as 2.18.8 or later, 2.21.4 or later, or the first fixed release in the applicable 2.22.x stream. For Jackson 3.x, upgrade to 3.1.4 or later, or the first fixed release in the applicable 3.2.x stream. If upgrading is not immediately possible, do not expose the non-blocking parser to untrusted, incrementally streamed JSON. Where feasible, use a synchronous parser or buffer and enforce strict request-size, connection-timeout, and concurrency limits at the ingress layer. Apply the upgrade as soon as possible because ingress limits reduce exposure but do not correct the parser defect.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | N/A |
| Attack Vector | Network | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | None | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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