---
id: CVE-2026-68494
title: >-
  The fix released in jackson-core 2.18.6 and 2.21.1 for CVE-2026-18401
  (GHSA-72hv-8253-57qq, number length constraint bypass in the non-blocking
  parser) is incomplete
summary: >-
  The fix released in jackson-core 2.18.6 and 2.21.1 for CVE-2026-18401
  (GHSA-72hv-8253-57qq, number length constraint bypass in the non-blocking
  parser) is incomplete. This record covers the remaining bypass.


  The earlier fix wired valida…
severity: high
cwe:
  - CWE-770
published: '2026-08-04'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T19:29:32.200'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-68494'
references:
  - url: >-
      https://github.com/FasterXML/jackson-core/commit/050b429804dce2a7e08f0be1b0b4c3d040fdb9cd
    label: 36c7be3b-2937-45df-85ea-ca7133ea542c
  - url: >-
      https://github.com/FasterXML/jackson-core/commit/4cdd529749da396cc7edf6d4a2aad41d47902641
    label: 36c7be3b-2937-45df-85ea-ca7133ea542c
  - url: >-
      https://github.com/FasterXML/jackson-core/commit/c5941e5aae7fd5aeac55d66933cfb82b9aabeef8
    label: 36c7be3b-2937-45df-85ea-ca7133ea542c
  - url: 'https://github.com/FasterXML/jackson-core/pull/1611'
    label: 36c7be3b-2937-45df-85ea-ca7133ea542c
  - url: >-
      https://github.com/FasterXML/jackson-core/security/advisories/GHSA-r7wm-3cxj-wff9
    label: 36c7be3b-2937-45df-85ea-ca7133ea542c
  - url: 'https://github.com/advisories/GHSA-72hv-8253-57qq'
    label: 36c7be3b-2937-45df-85ea-ca7133ea542c
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-18401'
    label: 36c7be3b-2937-45df-85ea-ca7133ea542c
  - url: >-
      https://github.com/FasterXML/jackson-core/security/advisories/GHSA-r7wm-3cxj-wff9
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-68494.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-68494'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2511026'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-68494'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-68494'
  - url: 'https://access.redhat.com/errata/RHSA-2026:53644'
  - url: 'https://access.redhat.com/errata/RHSA-2026:63327'
  - url: 'https://access.redhat.com/errata/RHSA-2026:63387'
  - url: 'https://access.redhat.com/errata/RHSA-2026:63386'
  - url: 'https://access.redhat.com/errata/RHSA-2026:63385'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60247'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60249'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60248'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60239'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60251'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60246'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60250'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60252'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60259'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60254'
  - url: 'https://access.redhat.com/errata/RHSA-2026:60256'
  - url: 'https://access.redhat.com/errata/RHSA-2026:53806'
  - url: 'https://access.redhat.com/errata/RHSA-2026:54440'
  - url: 'https://access.redhat.com/errata/RHSA-2026:66545'
  - url: 'https://access.redhat.com/errata/RHSA-2026:66488'
  - url: 'https://access.redhat.com/errata/RHSA-2026:68333'
  - url: 'https://access.redhat.com/errata/RHSA-2026:53645'
  - url: 'https://access.redhat.com/errata/RHSA-2026:53646'
  - url: 'https://access.redhat.com/errata/RHSA-2026:69459'
  - url: 'https://access.redhat.com/errata/RHSA-2026:70230'
  - url: 'https://access.redhat.com/errata/RHSA-2026:70228'
  - url: 'https://access.redhat.com/errata/RHSA-2026:70229'
tags:
  - nvd
  - csaf
  - vex
  - red-hat
epss: 0.00619
epssPercentile: 0.47375
ingestedAt: '2026-09-08T20:10:03.156Z'
vendor: Red Hat
product: Red Hat JBoss EAP 7.4 ELS for RHEL 7 Server
affected:
  - cryostat 4
  - exploit_intelligence
  - openshift_developer_tools_and_services
  - openshift_serverless
  - ai_inference_server
  - amq_broker 7
  - amq_clients
  - ansible_automation_platform 2
  - build_of_apache_camel_hawtio 4
  - build_of_apache_camel_4_for_quarkus 3
  - build_of_apache_camel_for_spring_boot 4
  - build_of_apicurio_registry 3
  - build_of_debezium 3
  - build_of_keycloak
  - ceph_storage 6
  - ceph_storage 7
  - ceph_storage 8
  - ceph_storage 9
  - certificate_system 10
  - certificate_system 11
  - data_grid 8
  - enterprise_linux 10
  - enterprise_linux 8
  - enterprise_linux 9
  - enterprise_linux_ai_rhel_ai 3
  - fuse 7
  - jboss_enterprise_application_platform 7
  - jboss_enterprise_application_platform 8
  - jboss_enterprise_application_platform_expansion_pack
  - jboss_web_server 7
  - openshift_ai_rhoai
  - openshift_dev_spaces
  - satellite 6
  - single_sign_on 7
  - streams_for_apache_kafka 2
  - streams_for_apache_kafka 3
  - jboss_eap_7_4_els_for_rhel_7_server
  - satellite_6_16_for_rhel 8
  - satellite_6_16_for_rhel 9
  - satellite_6_17_for_rhel 9
patched:
  - jboss_eap_7_4_els_for_rhel_7_server
  - satellite_6_16_for_rhel 8
  - satellite_6_16_for_rhel 9
  - satellite_6_17_for_rhel 9
  - satellite_6_18_for_rhel 9
  - satellite_6_19_for_rhel 9
  - openshift_developer_tools_and_services 4.12
  - openshift_developer_tools_and_services 4.13
  - openshift_developer_tools_and_services 4.14
  - openshift_developer_tools_and_services 4.15
  - openshift_developer_tools_and_services 4.16
  - openshift_developer_tools_and_services 4.17
  - openshift_developer_tools_and_services 4.18
  - openshift_developer_tools_and_services 4.19
  - openshift_developer_tools_and_services 4.20
  - openshift_developer_tools_and_services 4.21
  - openshift_developer_tools_and_services 4.22
  - jboss_enterprise_application_platform 7.4.25
  - lightspeed_formerly_insights_for_runtimes 1.0
  - openshift_ai 2.25
  - openshift_dev_spaces 3.30
  - build_of_quarkus 3.27.5
  - build_of_quarkus 3.33.3
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
---

## Overview

The fix released in jackson-core 2.18.6 and 2.21.1 for CVE-2026-18401 (GHSA-72hv-8253-57qq, number length constraint bypass in the non-blocking parser) is incomplete. This record covers the remaining bypass.

The earlier fix wired validateIntegerLength() into a new _setIntLength() helper and invoked it wherever the integer portion of a number is decided: a terminator byte arrives, a '.' or 'e'/'E' is seen, or input ends inside a fully buffered value. It was not invoked on the attacker-relevant path where the parser runs out of input while still inside the MINOR_NUMBER_INTEGER_DIGITS minor state and returns NOT_AVAILABLE to the caller.

As a result, an attacker who streams JSON to a non-blocking parser in many small chunks, without ever sending a terminator byte, keeps the parser inside MINOR_NUMBER_INTEGER_DIGITS indefinitely. _textBuffer.expandCurrentSegment() grows the accumulator on every chunk while validateIntegerLength() is never called. The accumulator is bounded only by maxStringLength (20 MiB by default) rather than by maxNumberLength (1000 by default), an amplification of roughly 20,000x over the documented limit. Because Java char values occupy two bytes, a single connection can be driven to approximately 40 MiB of heap before the validator finally fires when the value completes.

The equivalent fraction-path code is correct: _finishFloatFraction() calls _setFractLength() before its NOT_AVAILABLE return. The missing call affects the integer-digit paths in _startPositiveNumber(), _startNegativeNumber() and _finishNumberIntegralPart() in NonBlockingUtf8JsonParserBase.

Impact: reactive frameworks such as Spring WebFlux/Reactor, Quarkus, Helidon and Vert.x feed inbound HTTP or gRPC bytes to the async parser as they arrive, which is precisely the chunked-feed shape required. Operators who set StreamReadConstraints.maxNumberLength expecting it to cap memory per number value do not get that guarantee; memory accumulates per concurrent connection and attacker-controlled concurrency can exhaust the JVM heap. The synchronous parsers (UTF8StreamJsonParser, ReaderBasedJsonParser) and the async parser operating on complete input are not affected.

Exploitation requires only the ability to stream data to a parsing endpoint; no privileges or user interaction are needed.

This issue affects com.fasterxml.jackson.core:jackson-core from version 2.15.0 through 2.18.7, and from 2.19.0 through 2.21.3, and tools.jackson.core:jackson-core from 3.0.0 through 3.1.3. Versions prior to 2.15.0 are not affected, because StreamReadConstraints -- which defines the maxNumberLength setting -- was first introduced in jackson-core 2.15.0, so no such constraint exists to be bypassed in earlier releases. Note that GHSA-r7wm-3cxj-wff9 states the affected 2.x range without a lower bound. The 2.22.x and 3.2.x release lines are not affected: those branches were created after the fix commit landed on 2026-05-21 and therefore contain it from their initial releases (2.22.0, tagged 2026-06-03, and 3.2.0, tagged 2026-06-08).

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **RHSA-2026:53644** · Red Hat · fixed in: Red Hat JBoss EAP 7.4 ELS for RHEL 7 Server · released 2026-08-11 · [advisory](https://access.redhat.com/errata/RHSA-2026:53644)
- **RHSA-2026:63327** · Red Hat · fixed in: Red Hat Satellite 6.16 for RHEL 8, Red Hat Satellite 6.16 for RHEL 9 · released 2026-09-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:63327)
- **RHSA-2026:63387** · Red Hat · fixed in: Red Hat Satellite 6.17 for RHEL 9 · released 2026-09-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:63387)
- **RHSA-2026:63386** · Red Hat · fixed in: Red Hat Satellite 6.18 for RHEL 9 · released 2026-09-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:63386)
- **RHSA-2026:63385** · Red Hat · fixed in: Red Hat Satellite 6.19 for RHEL 9 · released 2026-09-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:63385)
- **RHSA-2026:60247** · Red Hat · fixed in: OpenShift Developer Tools and Services 4.12 · released 2026-08-26 · [advisory](https://access.redhat.com/errata/RHSA-2026:60247)
- **RHSA-2026:60249** · Red Hat · fixed in: OpenShift Developer Tools and Services 4.13 · released 2026-08-26 · [advisory](https://access.redhat.com/errata/RHSA-2026:60249)
- **RHSA-2026:60248** · Red Hat · fixed in: OpenShift Developer Tools and Services 4.14 · released 2026-08-26 · [advisory](https://access.redhat.com/errata/RHSA-2026:60248)
- **RHSA-2026:60239** · Red Hat · fixed in: OpenShift Developer Tools and Services 4.15 · released 2026-08-26 · [advisory](https://access.redhat.com/errata/RHSA-2026:60239)
- **RHSA-2026:60251** · Red Hat · fixed in: OpenShift Developer Tools and Services 4.16 · released 2026-08-26 · [advisory](https://access.redhat.com/errata/RHSA-2026:60251)
- **RHSA-2026:60246** · Red Hat · fixed in: OpenShift Developer Tools and Services 4.17 · released 2026-08-26 · [advisory](https://access.redhat.com/errata/RHSA-2026:60246)
- **Red Hat VEX** · Important · affected: Exploit Intelligence, OpenShift Developer Tools and Services, OpenShift Serverless, Red Hat AI Inference Server, Red Hat AMQ Broker 7, Red Hat build of Apache Camel - HawtIO 4, … · no fix planned: Red Hat AI Inference Server, Red Hat Data Grid 8, Red Hat Fuse 7, Exploit Intelligence, … · updated 2026-09-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-68494.json)
- **RHSA-2026:68333** · Red Hat · fixed in: Cryostat 4 on RHEL 9 · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68333)
- **RHSA-2026:53645** · Red Hat · fixed in: Red Hat JBoss EAP 7.4 ELS for RHEL 8 · released 2026-08-11 · [advisory](https://access.redhat.com/errata/RHSA-2026:53645)
- **RHSA-2026:53646** · Red Hat · fixed in: Red Hat JBoss EAP 7.4 ELS for RHEL 9 · released 2026-08-11 · [advisory](https://access.redhat.com/errata/RHSA-2026:53646)
- **RHSA-2026:69459** · Red Hat · fixed in: AMQ Clients 2026.Q3 · released 2026-09-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:69459)
- **RHSA-2026:70230** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 10 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70230)
- **RHSA-2026:70228** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 8 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70228)
- **RHSA-2026:70229** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 9 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70229)