Vulnerability in Uhop Stream-Json

CVE-2026-71429

stream-json is a micro-library of stream components for processing JSON and JSONC with a minimal memory footprint. Prior to 3.5.0, the path filters pick, ignore, filter, and replace in src/core/filters/filter-base.js recompute the full path string from the nesting stack for every checkable token. Because the stack length equals the current nesting depth and a checkable token is emitted at every level, a depth D document costs O(D²) rather than O(D) to process. The issue is triggered by nesting depth rather than byte volume, including the documented pick({filter: 'data'}) traversal-until-match path, so an application that sends untrusted JSON through a string or RegExp filter can block the Node.js event loop and cause denial of service with a small deeply nested document. The streamArray, streamObject, and streamValues streamers are not affected because they use the constant-time asm.depth getter. This issue is fixed in version 3.5.0.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.2 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.002 (4.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 5th percentile — 4.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-71429: held from 0.001 to 0.002.

EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-71429?
CVE-2026-71429 is a medium-severity vulnerability in Uhop Stream-Json, classified under Inefficient Algorithmic Complexity. CVSS score: 6.2/10. Published 2026-09-03.
How severe is CVE-2026-71429?
Medium severity. CVSS v3 base score is 6.2 out of 10.