Jackson Core does not consistently enforce StreamReadConstraints.maxDocumentLength. Oversized JSON documents can be accepted without a StreamConstraintsException in multiple parser entry points, which allows configured size limits to be bypassed and weakens denial-of-service protections. This advisory tracks the backport of GHSA-2m67-wjpj-xhg9 to the 2.18.x and 2.21.x release lines.
The non-blocking (async) JSON parser in jackson-core bypasses the maxNumberLength constraint (default: 1000 characters) defined in StreamReadConstraints. This allows an attacker to send JSON with arbitrarily long numbers through the async parser API, leading to excessive memory allocation and potential CPU exhaustion, resulting in a Denial of Service (DoS). The standard synchronous parser correctly enforces this limit, but the async parser fails to do so, creating an inconsistent enforcement policy.
With older versions of jackson-core, if you parse an input file and it has deeply nested data, Jackson could end up throwing a StackoverflowError if the depth is particularly large.
Overview A flaw in Jackson-core's JsonLocation._appendSourceDesc method allows up to 500 bytes of unintended memory content to be included in exception messages. When parsing JSON from a byte array with an offset and length, the exception message incorrectly reads from the beginning of the array instead of the logical payload start. This results in possible information disclosure in systems using pooled or reused buffers, like Netty or Vert.x. Details The …