One CBOR-parsing issue in jackson-dataformats-binary's CBOR module: an unbounded run of CBOR tags drives quadratic-time TagList growth (CPU/GC-exhaustion DoS, PoC-proven).
PoC executed against com.fasterxml.jackson.dataformat:jackson-dataformat-cbor:2.18.2; present in current 2.x and 3.x (tools.jackson.dataformat.cbor) HEAD. Distinct from the Avro and Smile/Protobuf advisories for this repo.
Quadratic CPU/GC DoS from an unbounded chain of CBOR tags (PoC-proven). File: cbor/src/main/java/.../cbor/CBORParser.java (tag handling -> TagList).
CBOR permits a data item to be preceded by any number of semantic tags. The CBOR parser accumulates them in a TagList whose backing array grows by a fixed increment (+8), not by doubling, and re-scans/copies on each growth. An attacker sends a value preceded by a long run of tag bytes; the fixed-increment growth makes accumulating N tags O(N^2) in time (plus GC pressure), with no cap on the number of stacked tags.
PoC (executed, JDK 17): feeding a CBOR stream consisting of a long run of tag bytes (e.g. tag 0xC0+) before a trivial value forces quadratic CPU/GC; parse time grows super-linearly with the tag count, pinning a request thread with no configurable limit.
Impact. Algorithmic-complexity denial of service (CWE-407): a modest input of stacked tags consumes quadratic CPU/GC, pinning a request thread; concurrent requests exhaust the pool.
Fix. Grow TagList by doubling and/or cap the number of stacked tags (StreamReadConstraints-style).
PoC executed against com.fasterxml.jackson.dataformat:jackson-dataformat-cbor:2.18.2; present in current 2.x and 3.x (tools.jackson.dataformat.cbor) HEAD. Distinct from the Avro and Smile/Protobuf advisories for this repo.
Quadratic CPU/GC DoS from an unbounded chain of CBOR tags (PoC-proven). File: cbor/src/main/java/.../cbor/CBORParser.java (tag handling -> TagList).
CBOR permits a data item to be preceded by any number of semantic tags. The CBOR parser accumulates them in a TagList whose backing array grows by a fixed increment (+8), not by doubling, and re-scans/copies on each growth. An attacker sends a value preceded by a long run of tag bytes; the fixed-increment growth makes accumulating N tags O(N^2) in time (plus GC pressure), with no cap on the number of stacked tags.
PoC (executed, JDK 17): feeding a CBOR stream consisting of a long run of tag bytes (e.g. tag 0xC0+) before a trivial value forces quadratic CPU/GC; parse time grows super-linearly with the tag count, pinning a request thread with no configurable limit.
Impact. Algorithmic-complexity denial of service (CWE-407): a modest input of stacked tags consumes quadratic CPU/GC, pinning a request thread; concurrent requests exhaust the pool.
Fix. Grow TagList by doubling and/or cap the number of stacked tags (StreamReadConstraints-style).
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| FasterXML | jackson-dataformat-cbor | unaffected |
|
|||||||||||||||||||||
| FasterXML | jackson-dataformat-cbor | unaffected |
|
No data.
No data.
OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.
No data.
Project Subscriptions
No data.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Wed, 04 Nov 2026 16:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | One CBOR-parsing issue in jackson-dataformats-binary's CBOR module: an unbounded run of CBOR tags drives quadratic-time TagList growth (CPU/GC-exhaustion DoS, PoC-proven). PoC executed against com.fasterxml.jackson.dataformat:jackson-dataformat-cbor:2.18.2; present in current 2.x and 3.x (tools.jackson.dataformat.cbor) HEAD. Distinct from the Avro and Smile/Protobuf advisories for this repo. Quadratic CPU/GC DoS from an unbounded chain of CBOR tags (PoC-proven). File: cbor/src/main/java/.../cbor/CBORParser.java (tag handling -> TagList). CBOR permits a data item to be preceded by any number of semantic tags. The CBOR parser accumulates them in a TagList whose backing array grows by a fixed increment (+8), not by doubling, and re-scans/copies on each growth. An attacker sends a value preceded by a long run of tag bytes; the fixed-increment growth makes accumulating N tags O(N^2) in time (plus GC pressure), with no cap on the number of stacked tags. PoC (executed, JDK 17): feeding a CBOR stream consisting of a long run of tag bytes (e.g. tag 0xC0+) before a trivial value forces quadratic CPU/GC; parse time grows super-linearly with the tag count, pinning a request thread with no configurable limit. Impact. Algorithmic-complexity denial of service (CWE-407): a modest input of stacked tags consumes quadratic CPU/GC, pinning a request thread; concurrent requests exhaust the pool. Fix. Grow TagList by doubling and/or cap the number of stacked tags (StreamReadConstraints-style). | |
| Title | jackson-dataformat-cbor: quadratic-time TagList growth on unbounded stacked tags (CPU/GC DoS, PoC) | |
| Weaknesses | CWE-407 | |
| References |
|
Projects
Sign in to view the affected projects.
MITRE
Status: PUBLISHED
Assigner: HeroDevs
Published:
Updated: 2026-11-04T16:14:05.664Z
Reserved: 2026-10-06T20:27:12.839Z
Link: CVE-2026-106554
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-11-04T16:17:32.640
Modified: 2026-11-04T16:17:32.640
Link: CVE-2026-106554
Redhat
No data.
OpenCVE Enrichment
Updated: 2026-11-04T18:15:13Z
Weaknesses