CVE-2026-104182

stream-json: JSONC parser and verifier re-scan the whole accumulated comment on every input chunk

Published Oct 1, 2026 CVSS 3.1 · 6.2 Medium EPSS < 1% KEV · Not listed
Description
stream-json is a micro-library of stream components for processing JSON and JSONC with a minimal memory footprint. Prior to 3.6.0, the JSONC parser at stream-json/jsonc/parser.js and verifier at stream-json/jsonc/verifier.js restart comment-terminator scanning from the opening slash whenever a block or line comment spans an input chunk, while retaining the accumulated comment buffer. Delivering a large valid comment across many small chunks therefore causes quadratic CPU work and can stall the Node.js event loop. The maintainer characterizes the attack vector as local because the documented JSONC input is locally owned or user-controlled configuration, rather than input intended for the open internet. This JSONC-only scope does not include the plain JSON parser, which advances through and discards consumed string and number data. This issue is fixed in version 3.6.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-hqr4-qq8f-hg3x stream-json: JSONC parser and verifier re-scan the whole accumulated comment on every input chunk
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Uhop
Uhop stream-json
Vendors & Products Uhop
Uhop stream-json
Type Values Removed Values Added
Description stream-json is a micro-library of stream components for processing JSON and JSONC with a minimal memory footprint. Prior to 3.6.0, the JSONC parser at stream-json/jsonc/parser.js and verifier at stream-json/jsonc/verifier.js restart comment-terminator scanning from the opening slash whenever a block or line comment spans an input chunk, while retaining the accumulated comment buffer. Delivering a large valid comment across many small chunks therefore causes quadratic CPU work and can stall the Node.js event loop. The maintainer characterizes the attack vector as local because the documented JSONC input is locally owned or user-controlled configuration, rather than input intended for the open internet. This JSONC-only scope does not include the plain JSON parser, which advances through and discards consumed string and number data. This issue is fixed in version 3.6.0.
Title stream-json: JSONC parser and verifier re-scan the whole accumulated comment on every input chunk
Weaknesses CWE-407
References
Metrics cvssV3_1

{'score': 6.2, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 5, 2026, 8:20 PM
Reserved
Oct 1, 2026, 6:54 PM
Status
Deferred
Published
Oct 1, 2026, 9:17 PM
Modified
Oct 5, 2026, 9:16 PM
Severity
Moderate
Public date
Oct 1, 2026, 8:15 PM