GHSA-6QM2-MCQ7-53QP: jackson-core Maven

PrioritiseCVE-2026-89425fasterxml · jackson-core +452 more1mo agojackson-core: UTF8DataInputJsonParser._reportInvalidToken() does not honor maxErrorTokenLength, allowing unbounded StringBuilder growthUTF8DataInputJsonParser._reportInvalidToken() in FasterXML jackson-core builds the offending-token text for its error message by appending Java identifier characters to a StringBuilder in a loop that has no upper bound. Unlike the three sibling parser implementations, including UTF8StreamJsonParser, it never consults ErrorReportConfiguration.getMaxErrorTokenLength() (default 256). A malformed token supplied to a parser created through JsonFactory.createParser(DataInput) is therefore accumulated in full. No StreamReadConstraints setting mitigates this: maxDocumentLength cannot be applied to DataInput sources at all, and maxStringLength does not cover this path because the accumulation bypasses ReadConstrainedTextBuffer. The reporter measured a 20,000,109-character exception message from a 20-million-character malformed token on the DataInput path, against 367 characters for identical input on the InputStream path. Scaling the payload drives the StringBuilder, which also incurs byte-to-char expansion and internal array doubling, to many times the raw payload size and can trigger OutOfMemoryError for the whole JVM. UTF8DataInputJsonParser was introduced in 2.8.0 together with createParser(DataInput); releases before 2.8.0 do not contain the affected class.CVSS7.5HighEPSS0.53%

PrioritiseCVE-2026-89407fasterxml · jackson-core +340 more1mo agojackson-core: quadratic backtracking in NumberInput.PATTERN_FLOAT via looksLikeValidNumber() enables ReDoSNumberInput.looksLikeValidNumber() in FasterXML jackson-core pre-validates "stringified numbers" with two regular expressions: PATTERN_FLOAT ([+-]?[0-9]*[\.]?[0-9]+([eE][+-]?[0-9]+)?), present since 2.17.0, and PATTERN_FLOAT_TRAILING_DOT, added in 2.17.2. PATTERN_FLOAT places adjacent quantifiers over the same character class -- an optional [0-9]* run, an optional dot, then a required [0-9]+ run -- so input that ultimately fails to match forces Java's backtracking engine to retry every possible split point of the digit run. Matching cost therefore grows with the square of the input length. An attacker who can supply JSON that an application deserializes into a numeric target type reaches this method through jackson-databind's default String-to-number coercion (StdDeserializer and NumberDeserializers for BigDecimal, BigInteger, Double and Float). Because StreamReadConstraints.maxStringLength defaults to 20,000,000 characters, no constraint bounds the input before it reaches the regex. Testing by the reporter confirmed O(n^2) growth across five consecutive input-size doublings, with a single 160,000-character string consuming roughly 74 seconds in one call; a small number of concurrent requests of ordinary body size can therefore exhaust a server's request-handling thread pool. The affected method does not exist before 2.17.0, so 2.16.x and earlier releases are not affected. The fix replaces both regular expressions with a hand-rolled single-pass scan.CVSS7.5HighEPSS0.63%

PrioritiseGHSA-642r-3gj9-2pj5Maventools.jackson.core · jackson-core3mo agotools.jackson.core jackson-coreDuplicate Advisory: jackson-core: Async parser maxNumberLength bypass via chunked digit accumulation (incomplete fix for GHSA-72hv-8253-57qq) ## Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-r7wm-3cxj-wff9. This link is maintained to preserve external references. ## Original 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, from 2.19.0 through 2.21.3, and from 2.22.0 through 2.22.0, and tools.jackson.core:jackson-core from 3.0.0 through 3.1.3 and from 3.2.0 through 3.2.0. 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.CVSSUnscored

PrioritiseCVE-2026-68494fasterxml · jackson-core +383 more3mo agojackson-core: Async parser maxNumberLength bypass via chunked digit accumulation (incomplete fix for CVE-2026-18401 / GHSA-72hv-8253-57qq)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).CVSS8.7HighEPSS0.46%

RoutineCVE-2026-18401fasterxml · jackson-core +515 more3mo agojackson-core: Number length constraint bypass in non-blocking (async) JSON parser leads to potential denial of serviceThe non-blocking (asynchronous) JSON parser in jackson-core does not enforce the maxNumberLength constraint defined in StreamReadConstraints (default: 1000 characters). An attacker able to submit JSON to an application that uses the async parser API can supply a number token of arbitrary length, leading to excessive memory allocation and potential CPU exhaustion, resulting in a denial of service. The synchronous parser enforces this limit correctly, so the constraint is applied inconsistently depending on which parsing API the application uses. Root cause: the async parsing path in NonBlockingUtf8JsonParserBase and related classes never invokes the number length validation methods. Number parsing methods such as _finishNumberIntegralPart() accumulate digits into the TextBuffer without any length check, then call _valueComplete() to finalize the token. _valueComplete() does not call resetInt() or resetFloat(), which are the methods in ParserBase where validateIntegerLength() and validateFPLength() are performed. Because that validation step is skipped, maxNumberLength is never enforced on the async code path. Impact: an attacker sending a JSON document containing an arbitrarily long number to an application using the async parser (for example a Spring WebFlux or other reactive application) can cause unbounded allocation in the TextBuffer and an OutOfMemoryError. If the application subsequently calls getBigIntegerValue() or getDecimalValue(), the JVM may additionally be tied up in O(n^2) BigInteger parsing, causing CPU-based denial of service. No privileges or user interaction beyond the ability to submit data for parsing are required. This issue affects com.fasterxml.jackson.core:jackson-core from version 2.15.0 through 2.18.5 and from 2.19.0 through 2.21.0, and tools.jackson.core:jackson-core from 3.0.0 through 3.0.x. 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-72hv-8253-57qq records the lower bound of the affected 2.x range as 2.0.0.CVSS6.9MediumEPSS0.41%

PrioritiseGHSA-2m67-wjpj-xhg9Maventools.jackson.core · jackson-core7mo agotools.jackson.core jackson-coreJackson Core: Document length constraint bypass in blocking, async, and DataInput parsers ## Summary Jackson Core 3.x 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. ## Details Three code paths where `maxDocumentLength` is not fully enforced: ### 1. Blocking parsers skip validation of the final in-memory buffer Blocking parsers validate only previously processed buffers, not the final in-memory buffer: - `ReaderBasedJsonParser.java:255` - `UTF8StreamJsonParser.java:208` Relevant code: ```java _currInputProcessed += bufSize; _streamReadConstraints.validateDocumentLength(_currInputProcessed); ``` This means the check occurs only when a completed buffer is rolled over. If an oversized document is fully contained in the final buffer, parsing can complete without any document-length exception. ### 2. Async parsers skip validation of the final chunk on end-of-input Async parsers validate previously processed chunks, but do not validate the final chunk on end-of-input: - `NonBlockingByteArrayJsonParser.java:49` - `NonBlockingByteBufferJsonParser.java:57` - `NonBlockingUtf8JsonParserBase.java:75` Relevant code: ```java _currInputProcessed += _origBufferLen; _streamReadConstraints.validateDocumentLength(_currInputProcessed); public void endOfInput() { _endOfInput = true; } ``` `endOfInput()` marks EOF but does not perform a final `validateDocumentLength(...)` call, so an oversized last chunk is accepted. ### 3. DataInput parser path does not enforce `maxDocumentLength` at all - `JsonFactory.java:457` Relevant construction path: ```java int firstByte = ByteSourceJsonBootstrapper.skipUTF8BOM(input); return new UTF8DataInputJsonParser(readCtxt, ioCtxt, readCtxt.getStreamReadFeatures(_streamReadFeatures), readCtxt.getFormatReadFeatures(_formatReadFeatures), input, can, firstByte); ``` `UTF8DataInputJsonParser` does not call `StreamReadConstraints.validateDocumentLength(...)`, so `maxDocumentLength` is effectively disabled for `createParser(..., DataInput)` users. > **Note:** This issue appears distinct from the recently published nesting-depth and number-length constraint advisories because it affects document-length enforcement. ## PoC ### Async path reproducer ```java import java.nio.charset.StandardCharsets; import tools.jackson.core.JsonParser; import tools.jackson.core.ObjectReadContext; import tools.jackson.core.StreamReadConstraints; import tools.jackson.core.async.ByteArrayFeeder; import tools.jackson.core.json.JsonFactory; public class Poc { public static void main(String[] args) throws Exception { JsonFactory factory = JsonFactory.builder() .streamReadConstraints(StreamReadConstraints.builder() .maxDocumentLength(10L) .build()) .build(); byte[] doc = "{\"a\":1,\"b\":2}".getBytes(StandardCharsets.UTF_8); try (JsonParser p = factory.createNonBlockingByteArrayParser(ObjectReadContext.empty())) { ByteArrayFeeder feeder = (ByteArrayFeeder) p.nonBlockingInputFeeder(); feeder.feedInput(doc, 0, doc.length); feeder.endOfInput(); while (p.nextToken() != null) { } } System.out.println("Parsed successfully"); } } ``` - **Expected result:** Parsing should fail because the configured document-length limit is 10, while the input is longer than 10 bytes. - **Actual result:** The document is accepted and parsing completes. ### Blocking path reproducer ```java import java.io.ByteArrayInputStream; import java.nio.charset.StandardCharsets; import tools.jackson.core.JsonParser; import tools.jackson.core.StreamReadConstraints; import tools.jackson.core.json.JsonFactory; public class Poc2 { public static void main(String[] args) throws Exception { JsonFactory factory = JsonFactory.builder() .streamReadConstraints(StreamReadConstraints.builder() .maxDocumentLength(10L) .build()) .build(); byte[] doc = "{\"a\":1,\"b\":2}".getBytes(StandardCharsets.UTF_8); try (JsonParser p = factory.createParser(new ByteArrayInputStream(doc))) { while (p.nextToken() != null) { } } System.out.println("Parsed successfully"); } } ``` ## Impact Applications that rely on `maxDocumentLength` as a safety control for untrusted JSON can accept oversized inputs without error. In network-facing services this weakens an explicit denial-of-service protection and can increase CPU and memory consumption by allowing larger-than-configured request bodies to be processed.CVSSUnscored

GHSA-6QM2-MCQ7-53QP: jackson-core Maven

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