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TI-2026-85107 Aliases CVE-2026-106554

jackson-dataformat-cbor: quadratic TagList growth from unbounded CBOR tags

Priority LOW 22CWE-407Published · Updated

Key facts

Attack vector
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Privileges required
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User interaction
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Attack complexity
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Impact type
Denial of service
Confidentiality · integrity · availability
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Fix status
Partial Red Hat: 9 without a fix

No CVSS vector from any source. Fix status from CNA and Red Hat. Impact type from CWE-407.

Summary

The CBOR parser in jackson-dataformat-cbor stores semantic tags in a TagList that grows by a fixed increment of 8 and copies its contents on each growth. An attacker can send a value preceded by an unbounded run of tags, and accumulating them takes quadratic time and extra GC work, which enables denial of service (CWE-407). A proof of concept run against 2.18.2 showed parse time rising super-linearly with the tag count, pinning a request thread with no configurable limit.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

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).

Why it matters now

EPSS 0.00177 7th percentileScored 2026-11-07
Fix Partial jackson-dataformat-cbor (FasterXML): 2.18.12, 2.21.8, 2.22.4 +2Red Hat: 9 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
FasterXMLjackson-dataformat-cbor2.15.0 to before 2.18.12; 2.19.0 to before 2.21.8; 2.22.0 to before 2.22.42.18.12, 2.21.8, 2.22.4Patch availableCNA
FasterXMLjackson-dataformat-cbor3.0.0 to before 3.1.8; 3.2.0 to before 3.2.43.1.8, 3.2.4Patch availableCNA
  • jackson-dataformat-cbor VendorFasterXML Affected 2.15.0 to before 2.18.12; 2.19.0 to before 2.21.8; 2.22.0 to before 2.22.4 Fixed in 2.18.12, 2.21.8, 2.22.4 Patch available CNA
  • jackson-dataformat-cbor VendorFasterXML Affected 3.0.0 to before 3.1.8; 3.2.0 to before 3.2.4 Fixed in 3.1.8, 3.2.4 Patch available CNA

Remediation

Upgrade to a fixed release: 2.18.12, 2.21.8 or 2.22.4 on the 2.x line, or 3.1.8 or 3.2.4 on the 3.x line. Red Hat rates this Important and lists Red Hat Enterprise Linux 8 and 9 among the products still affected without a fix.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA jackson-dataformat-cbor (FasterXML) Fixed in 2.18.12, 2.21.8, 2.22.4
  • Fix · CNA jackson-dataformat-cbor (FasterXML) Fixed in 3.1.8, 3.2.4

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
OpenShift Developer Tools and ServicesAffected—
Red Hat Build of KeycloakAffected—
Red Hat Enterprise Linux 8Affected—
Red Hat Enterprise Linux 9Affected—
Red Hat Fuse 7Affected—
Red Hat Offline Knowledge PortalAffected—
Red Hat Satellite 6Affected—
Red Hat Single Sign-On 7Affected—
Red Hat build of Apache Camel for Spring Boot 4Affected—

Timeline

  1. 2026-11-04 Threatist record created from CVE-2026-106554
  2. 2026-11-06 Affected versions changed · Red Hat
  3. 2026-11-06 CVSS score added · Red Hat

References

  • TI-2017-12774 FasterXML jackson-databind through 2.8.10 and 2.9.x through 2.9.3 allows unauthenticated… CVSS 3.1CRITICAL 9.8
  • TI-2026-48269 Resource allocation without limits in FasterXML jackson-core CVSS 4.0HIGH 8.7
  • TI-2017-05167 Deserialization of untrusted data in FasterXML jackson-databind CVSS 3.1CRITICAL 9.8
  • TI-2026-61988 jackson-databind: quadratic forward-reference completion in Collection and Map deserializers CVSS 3.1HIGH 7.5
  • TI-2026-61987 jackson-databind: unbounded growth of the type id cache in TypeDeserializerBase retains every unknown raw type ID CVSS 3.1HIGH 7.5
  • TI-2026-60476 Uncontrolled resource consumption in FasterXML jackson-core CVSS 3.1HIGH 7.5
See all 107 →

Sources