CVE-2026-91777

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in FasterXML Jackson ausnutzen, um einen Denial of Service Angriff durchzuführen.

Ein Angreifer kann mehrere Schwachstellen in SOS GmbH JobScheduler ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.

### Summary When an `@JsonIdentityInfo` collection or map first creates N unresolved object-ID references and later resolves the same IDs in reverse order, jackson-databind scans the remaining pending-reference accumulator for each resolution. A shallow JSON document whose size grows linearly can therefore cause quadratic CPU work during deserialization. ### Details The affected path is forward-reference completion in `CollectionDeserializer.CollectionReferringAccumulator.resolveForwardReference()` and the corresponding map implementation. The implementation performs a linear search of the pending accumulator for every resolved object ID. The behavior is runtime-confirmed in jackson-databind 2.5.0, 2.22.1, and 3.2.1. Current 2.22 and 3.2 source branches retained the same design when rechecked. A 2.4.0 control fails closed before successful reverse-order completion, so 2.5.0 is the conservative runtime-confirmed affected floor. The patched versions are: 2.18.11, 2.21.7, 2.22.3, 3.1.7 and 3.2.3. The vulnerable application must deserialize attacker-influenced JSON into an identity-enabled collection or map. The issue does not require deep nesting or syntactically unusual JSON. Suggested correction: replace repeated linear lookup/removal with a keyed pending-reference structure or another design that provides linear or amortized-linear completion. A regression should preserve input order, duplicate-ID behavior, and unresolved-ID errors while bounding reverse-order resolution work. ### PoC The proof constructs a shallow collection containing N unresolved `@JsonIdentityInfo` references followed by definitions of those same IDs in reverse order. Its ID class counts `equals()` calls, giving a deterministic work measure rather than a timing-dependent result. With N=2,000, affected versions perform exactly 2,003,000 ID comparisons. An equally sized control in which every reference is already resolved performs zero comparisons in the pending-reference lookup path. The run is bounded to a 512 MiB JVM. The result demonstrates quadratic growth: approximately `N * (N + 1) / 2` comparisons, plus fixed setup comparisons. ### Impact An unauthenticated source that can submit JSON to an application using the affected identity-enabled collection or map shape can consume quadratic CPU and exhaust a request-time or worker-capacity budget, causing denial of service. The application model/configuration prerequisite is material. No confidentiality, integrity, code-execution, or parser-depth impact is claimed. Requested credit: Daniel Birtwhistle