Security Bulletin: IBM App Connect Enterprise and IBM Integration Bus for z/OS are vulnerable to multiple vulnerabilities due to jackson-databind

Vulnerability Details

CVEID:   CVE-2026-54512
DESCRIPTION:   jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.10.0 until 2.18.8, 2.21.4, and 3.1.4, jackson-databind's PolymorphicTypeValidator (PTV) is the primary safety mechanism guarding polymorphic deserialization. When polymorphic typing is enabled and a type identifier contains generic parameters (i.e. the type ID string contains ), DatabindContext._resolveAndValidateGeneric() validates only the raw container class name (the substring before ) against the configured PTV. If the container type is approved, the method parses the full canonical type string via TypeFactory.constructFromCanonical() and returns the fully parameterized type without ever validating the nested type arguments against the PTV. The nested type arguments are then resolved, instantiated, and populated as beans during deserialization. An attacker who controls the type ID can therefore place a denied class as a generic type parameter of an allowed container — for example java.util.ArrayListcom.evil.Gadget when only java.util.ArrayList is allow-listed. The container passes the PTV check; com.evil.Gadget is loaded via Class.forName(name, true, loader), instantiated, and its properties are set from attacker-controlled JSON. This completely bypasses an explicitly configured PTV allow-list. This vulnerability is fixed in 2.18.8, 2.21.4, and 3.1.4.
CWE:   CWE-184: Incomplete List of Disallowed Inputs
CVSS Source:   security-advisories@github.com
CVSS Base score:   8.1
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H)

CVEID:   CVE-2026-54513
DESCRIPTION:   jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.10.0 until 2.18.8, 2.21.4, and 3.1.4, BasicPolymorphicTypeValidator.Builder.allowIfSubTypeIsArray() allowlists any array type based only on clazz.isArray(), without validating the array's component (element) type against the configured allowlist. A PTV built with allowIfSubTypeIsArray() plus an explicit concrete-type allowlist therefore still permits EvilType[] even though EvilType is not allowlisted. When Jackson deserializes the elements and no per-element type IDs are present, it instantiates the component type directly with no further PTV check, bypassing the allowlist. This vulnerability is fixed in 2.18.8, 2.21.4, and 3.1.4.
CWE:   CWE-184: Incomplete List of Disallowed Inputs
CVSS Source:   security-advisories@github.com
CVSS Base score:   8.1
CVSS Vector:   (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H)

CVEID:   CVE-2026-54514
DESCRIPTION:   jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.0.0 until 2.18.8, 2.21.4, and 3.1.4, JDKFromStringDeserializer constructed InetSocketAddress with new InetSocketAddress(host, port), which performs eager DNS name resolution for hostname inputs at deserialization time. An application that binds untrusted JSON into a type containing an InetSocketAddress field issues an attacker-chosen DNS query during readValue, before any application-level validation or connect logic. The fix uses InetSocketAddress.createUnresolved(host, port), deferring DNS to an explicit connect. This vulnerability is fixed in 2.18.8, 2.21.4, and 3.1.4.
CWE:   CWE-918: Server-Side Request Forgery (SSRF)
CVSS Source:   security-advisories@github.com
CVSS Base score:   5.3
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)

CVEID:   CVE-2026-54515
DESCRIPTION:   jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.8.0 until 2.18.9, 2.21.5, and 3.1.4, in BeanDeserializerBase.createContextual(), per-property @JsonIgnoreProperties exclusions are applied by _handleByNameInclusion(), producing a contextual deserializer whose BeanPropertyMap has the ignored properties removed. The subsequent per-property case-insensitivity block (triggered by @JsonFormat(ACCEPT_CASE_INSENSITIVE_PROPERTIES)) rebuilds from this._beanProperties (the original, unfiltered map) instead of contextual._beanProperties, then overwrites the filtered map — restoring every property _handleByNameInclusion had just removed. The ignored property becomes writable again. This vulnerability is fixed in 2.18.9, 2.21.5, and 3.1.4.
CWE:   CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes
CVSS Source:   security-advisories@github.com
CVSS Base score:   5.3
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)

CVEID:   CVE-2026-54516
DESCRIPTION:   jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.21.0 until 2.21.4 and 3.1.4, POJOPropertiesCollector._renameProperties() allows a property with @JsonProperty("renamed") on the getter and @JsonIgnore on the setter to be renamed rather than dropped. With MapperFeature.INFER_PROPERTY_MUTATORS enabled (default), the private backing field is retained; during deserialization BeanDeserializerFactory.addBeanProps() sees hasField()==true, builds a FieldProperty, and makes the backing field writable. An attacker supplying the renamed JSON key writes the backing field directly, bypassing the @JsonIgnore on the setter. This vulnerability is fixed in 3.1.4.
CWE:   CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes
CVSS Source:   Github
CVSS Base score:   5.3
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)

CVEID:   CVE-2026-54517
DESCRIPTION:   jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.21.0 until 2.21.4 and 3.1.4, in BeanDeserializer._deserializeUsingPropertyBased, the active-view (@JsonView) filter was applied only to creator properties; the regular property-buffering branch performed no prop.visibleInView(activeView) check. A change making SetterlessProperty.isMerging() return true routed setterless Collection/Map properties through this unguarded path, so a setterless collection annotated with a restricted @JsonView is populated from attacker JSON even when the active view excludes it. This vulnerability is fixed in 2.21.4 and 3.1.4.
CWE:   CWE-863: Incorrect Authorization
CVSS Source:   Github
CVSS Base score:   5.3
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)

CVEID:   CVE-2026-54518
DESCRIPTION:   jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.21.0 until 2.21.4 and 3.1.4, UnwrappedPropertyHandler.processUnwrappedCreatorProperties() replays buffered JSON into creator parameters but never consults prop.visibleInView(activeView). The normal property-based creator path gates creator properties on the active view, but this unwrapped-creator replay path bypasses that check, so a constructor parameter annotated with both @JsonView(AdminView.class) and @JsonUnwrapped is populated from attacker JSON even when a more restrictive view is active. This vulnerability is fixed in 2.21.4 and 3.1.4.
CWE:   CWE-863: Incorrect Authorization
CVSS Source:   Github
CVSS Base score:   6.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N)

CVEID:   CVE-2026-59888
DESCRIPTION:   jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.15.0 until 2.18.8, 2.21.4, and 3.1.4, Java Records using a PropertyNamingStrategy can bypass @JsonIgnore because POJOPropertiesCollector._removeUnwantedIgnorals() records an ignored component under its original implicit name before _renameUsing() applies the naming strategy, allowing the renamed JSON key to be assigned to the Record constructor parameter. This issue is fixed in versions 2.18.8, 2.21.4, and 3.1.4.
CWE:   CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes
CVSS Source:   security-advisories@github.com
CVSS Base score:   6.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N)

CVEID:   CVE-2026-59889
DESCRIPTION:   jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.18.0 until 2.18.9, 2.21.5, 2.22.1, 3.1.5, and 3.2.1, UnwrappedPropertyHandler.processUnwrapped() replays buffered JSON for a @JsonUnwrapped property and calls prop.deserializeAndSet() without a prop.visibleInView(ctxt.getActiveView()) guard, allowing a property annotated with both @JsonView and @JsonUnwrapped to be written from attacker JSON under a less-privileged active view. This issue is fixed in versions 2.18.9, 2.21.5, 2.22.1, 3.1.5, and 3.2.1.
CWE:   CWE-863: Incorrect Authorization
CVSS Source:   security-advisories@github.com
CVSS Base score:   6.5
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N)

CVEID:   CVE-2026-77310
DESCRIPTION:   jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. Prior to versions 2.18.9, 2.21.5, 2.22.1, 3.1.5, and 3.2.1 on their respective release lines, the java.net.InetAddress branch of FromStringDeserializer.Std._deserialize() calls InetAddress.getByName() on attacker-controlled input, causing eager DNS resolution during deserialization and enabling DNS-based server-side request forgery and internal-host enumeration. This issue is fixed in versions 2.18.9, 2.21.5, 2.22.1, 3.1.5, and 3.2.1.
CWE:   CWE-918: Server-Side Request Forgery (SSRF)
CVSS Source:   security-advisories@github.com
CVSS Base score:   5.3
CVSS Vector:   (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)

CVEID:   CVE-2026-68494
DESCRIPTION:   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).
CWE:   CWE-770: Allocation of Resources Without Limits or Throttling
CVSS Source:   HeroDevs
CVSS Base score:   8.7
CVSS Vector:   (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X)