CVE-2026-114129: medium-severity vulnerability in uhop stream-json
stream-json: FlexAssembler string/RegExp path filters join the full key stack per container start, giving O(depth^2) CPU denial of service
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.2epss 0.3%
stream-json is a micro-library of stream components for processing JSON and JSONC with a minimal memory footprint. From 2.0.0 until 3.7.0, FlexAssembler compiles string and regular-expression path filters into matchers that join the full key stack on every container start. Because the key stack grows with unbounded object or array nesting, a document nested to depth D causes D joins whose cost grows with the current depth, resulting in quadratic CPU consumption on the single-threaded event loop. The join occurs before the rule match decision, so the attacker does not need to know the target schema. Consumers using only function filters or no rules are not affected. A crafted nested document can stall all concurrent work in a process that feeds it to an affected FlexAssembler. This issue is fixed in 3.7.0, which adds a default maximum depth.
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
uhop · stream-jsonRelated CVEs — uhop stream-json
In the same product, most dangerous first.
CVE-2026-104182MEDIUMstream-json: JSONC parser and verifier re-scan the whole accumulated comment on every input chunkEPSS 0.2%CVE-2026-104183MEDIUMstream-json: Prototype pollution: Assembler writes this.current[this.key] on plain objectsEPSS 0.2%CVE-2026-71429MEDIUMstream-json: pick/ignore/filter/replace filters are O(depth²) on nested input — small crafted JSON blocks the event loop for seconds→minutes (DoS)EPSS 0.2%
References
https://github.com/uhop/stream-json/commit/1929fd80495d45b47e8f8cb1d4e132f915aef012https://github.com/uhop/stream-json/commit/c06c9a3c02adef89543e26ecebb45837cb284512https://github.com/uhop/stream-json/releases/tag/3.7.0https://github.com/uhop/stream-json/security/advisories/GHSA-jj87-hc4r-jwfw