---
title: "CVE-2026-10032: @a2ui/web_core: `openUrl` permits `javascript:` URI execution via agent-supplied button actions"
url: https://erroneo.us/security/cve/CVE-2026-10032/
description: "CVE-2026-10032 (@a2ui/web_core (npm)): The openUrl function in @a2ui/webcore passes an agent-controlled URL directly to window.open() without validating the…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-08-04
date_modified: 2026-10-02
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-10032"
kev: false
cvss: 6.1
epss: 0.00125
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-10032: @a2ui/web_core: `openUrl` permits `javascript:` URI execution via agent-supplied button actions

**Signal:** Normal patch cycle. No exploitation signal; fix it in your next routine update if you are affected. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.1% , percentile 2: FIRST’s model estimates a 0.1% chance of exploitation activity in the next 30 days, higher than 2% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). Exposure depends on who can log in.
- Only applies if your dependency tree includes @a2ui/web_core (npm) >= 0.9.0, < 0.10.2, fixed in 0.10.2 . Check your lockfile, including transitive dependencies.

## What it is

The openUrl function in @a2ui/webcore passes an agent-controlled URL directly to window.open() without validating the URI scheme. A malicious agent can supply a javascript: URI as the url argument of a Button component's functionCall action. When the user clicks the rendered button, arbitrary JavaScript executes in the victim application's browser origin, constituting a stored/reflected XSS with Critical severity. No non-default configuration is required; the Basic Catalog is enabled by default.

## Affected packages

- npm `@a2ui/web_core` >= 0.9.0, < 0.10.2 → fixed: 0.10.2

## Affected products (CVE record)

- Google @a2ui/web_core: 0.9.0, 0.9.1-alpha.0, 0.9.1-alpha.1, 0.9.1-alpha.2, 0.9.1-alpha.3, 0.9.1-alpha.4, 0.9.1-alpha.5, 0.9.1, 0.9.2, 0.10.0, 0.10.1

## Severity

- Google CVSS 4.0: 6.1 `CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:U`
- GitHub CVSS 3.1: 9.3 `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.12% probability of exploitation activity in the next 30 days; percentile 2.

## Sources

- [GitHub Advisory GHSA-72qq-p3r5-f7wq](https://github.com/advisories/GHSA-72qq-p3r5-f7wq)
- [CVE.org record CVE-2026-10032](https://www.cve.org/CVERecord?id=CVE-2026-10032)
- [NVD entry CVE-2026-10032](https://nvd.nist.gov/vuln/detail/CVE-2026-10032)
- [github.com](https://github.com/a2ui-project/a2ui/security/advisories/GHSA-72qq-p3r5-f7wq)
- [github.com](https://github.com/a2ui-project/a2ui/pull/1707)
- [github.com](https://github.com/a2ui-project/a2ui/commit/71573078c4168b2dc166bb847c3a85715dadc675)

---
Source page: https://erroneo.us/security/cve/CVE-2026-10032/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt