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.
https://github.com/FasterXML/jackson-databind/security/advisories/GHSA-5jmj-h7xm-6q6v
https://github.com/FasterXML/jackson-databind/issues/5964
https://github.com/FasterXML/jackson-databind/issues/5962
https://github.com/FasterXML/jackson-databind/commit/0e1b0b211f7a53baa62ba2f4c9bd006c7bf4d5fa