Jackson Release 3.1.2

Patch version of 3.1, released on April 11, 2026.

Following fixes are included in this patch release.

Changes, core

Streaming

• #1561: Javadoc for 3.1.0 doesn't work (build with JDK 21)

Databind

• #5857: TypeFactory._fromParamType StackOverflowError with mutually recursive generic bounds (regression in 3.1.0)
• #5865: @JsonIgnoreProperties does not work alongside DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES
• #5867: Fix Map.Entry deserialization for property-level Shape.NATURAL override
• #5870: EnumMap and EnumSet properties ignore @JsonDeserialize(contentConverter)
• #5884: Exception when using @JsonUnwrapped alongside with @JsonAlias on another property
• #5891: EnumMapDeserializer._deserializeUsingProperties() corrupts parser state after skipping unknown enum keys

Changes, data formats

CBOR

• #686: CBORParser._finishLongTextAscii returns negative length when TextBuffer segment > I/O buffer, leaving non-ASCII byte unconsumed