{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-106554","assignerOrgId":"36c7be3b-2937-45df-85ea-ca7133ea542c","state":"PUBLISHED","assignerShortName":"HeroDevs","dateReserved":"2026-10-06T20:27:12.839Z","datePublished":"2026-11-04T16:14:05.664Z","dateUpdated":"2026-11-04T16:14:05.664Z"},"containers":{"cna":{"providerMetadata":{"orgId":"36c7be3b-2937-45df-85ea-ca7133ea542c","shortName":"HeroDevs","dateUpdated":"2026-11-04T16:14:05.664Z"},"title":"jackson-dataformat-cbor: quadratic-time TagList growth on unbounded stacked tags (CPU/GC DoS, PoC)","problemTypes":[{"descriptions":[{"lang":"en","cweId":"CWE-407","description":"CWE-407 Inefficient Algorithmic Complexity","type":"CWE"}]}],"affected":[{"vendor":"FasterXML","product":"jackson-dataformat-cbor","collectionURL":"https://repo.maven.apache.org/maven2","packageName":"com.fasterxml.jackson.dataformat:jackson-dataformat-cbor","repo":"https://github.com/FasterXML/jackson-dataformats-binary","programFiles":["cbor/src/main/java/.../cbor/CBORParser.java"],"programRoutines":[{"name":"CBORParser (tag handling -> TagList)"}],"versions":[{"status":"affected","version":"2.15.0","lessThan":"2.18.12","versionType":"maven"},{"status":"unaffected","version":"2.18.12","versionType":"maven"},{"status":"affected","version":"2.19.0","lessThan":"2.21.8","versionType":"maven"},{"status":"unaffected","version":"2.21.8","versionType":"maven"},{"status":"affected","version":"2.22.0","lessThan":"2.22.4","versionType":"maven"},{"status":"unaffected","version":"2.22.4","versionType":"maven"}],"defaultStatus":"unaffected"},{"vendor":"FasterXML","product":"jackson-dataformat-cbor","collectionURL":"https://repo.maven.apache.org/maven2","packageName":"tools.jackson.dataformat:jackson-dataformat-cbor","repo":"https://github.com/FasterXML/jackson-dataformats-binary","programFiles":["cbor/src/main/java/.../cbor/CBORParser.java"],"programRoutines":[{"name":"CBORParser (tag handling -> TagList)"}],"versions":[{"status":"affected","version":"3.0.0","lessThan":"3.1.8","versionType":"maven"},{"status":"unaffected","version":"3.1.8","versionType":"maven"},{"status":"affected","version":"3.2.0","lessThan":"3.2.4","versionType":"maven"},{"status":"unaffected","version":"3.2.4","versionType":"maven"}],"defaultStatus":"unaffected"}],"descriptions":[{"lang":"en","value":"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).\n\n\n\nPoC 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.\n\n\n\nQuadratic CPU/GC DoS from an unbounded chain of CBOR tags (PoC-proven). File: cbor/src/main/java/.../cbor/CBORParser.java (tag handling -> TagList).\n\n\n\nCBOR 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.\n\n\n\nPoC (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.\n\n\n\nImpact. 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.\n\n\n\nFix. Grow TagList by doubling and/or cap the number of stacked tags (StreamReadConstraints-style).","supportingMedia":[{"type":"text/html","base64":false,"value":"<p>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).</p><p>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.</p><p>Quadratic CPU/GC DoS from an unbounded chain of CBOR tags (PoC-proven). File: cbor/src/main/java/.../cbor/CBORParser.java (tag handling -&gt; TagList).</p><p>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.</p><p>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.</p><p>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.</p><p>Fix. Grow TagList by doubling and/or cap the number of stacked tags (StreamReadConstraints-style).</p>"}]}],"tags":["x_open-source"],"references":[{"url":"https://github.com/FasterXML/jackson-dataformats-binary/security/advisories/GHSA-cjg7-h3pr-p927","name":"GHSA-cjg7-h3pr-p927","tags":["vendor-advisory"]}],"metrics":[{"other":{"type":"severity","content":{"text":"MEDIUM"}},"format":"other","scenarios":[{"lang":"en","value":"GENERAL"}]}],"timeline":[{"time":"2026-10-22T21:30:00.000Z","lang":"en","value":"GHSA-cjg7-h3pr-p927 published in FasterXML/jackson-dataformats-binary"}],"credits":[{"lang":"en","value":"apvxlab (AppViewX security research)","type":"reporter"},{"lang":"en","value":"v0xyc0n (www.jpac.at)","type":"reporter"}],"source":{"advisory":"GHSA-cjg7-h3pr-p927","discovery":"EXTERNAL"},"x_generator":{"engine":"Vulnogram 0.5.0"}}}}