Summarize's hover summary feature allows malicious pages to dispatch synthetic mouseover events over attacker-controlled links

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

4.6 · CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:L/VI:N/VA:N/SC:H/SI:N/SA:N · score source

EPSS

• CVE-2026-45245: 0.33% estimated exploitation activity in the next 30 days; percentile 26.19 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summarize prior to 0.15.0 contains a vulnerability in the hover summary feature that allows malicious pages to dispatch synthetic mouseover events over attacker-controlled links, causing the extension to make authenticated daemon requests using stored tokens without verifying event trustworthiness. Attackers can place local or private-network URLs behind hoverable links to route authenticated requests through the daemon, potentially accessing sensitive internal endpoints when users interact with attacker-controlled content.

Published by the source

18 May 2026, 21:31 UTC

Last modified by the source

10 Sep 2026, 03:51 UTC

Source last checked

26 Oct 2026, 12:52 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-2r69-qgv3-hr65

2. Revision 2 · amended · 24 Oct 2026

   Reviewed OSV alias/range/CVSS4 correction; package source scopes and original publication preserved. No customer finding resolved.

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-2r69-qgv3-hr65

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# Patch Next advisory brief: CVE-2026-45245

Advisory: Summarize's hover summary feature allows malicious pages to dispatch synthetic mouseover events over attacker-controlled links
IDs: CVE-2026-45245, GHSA-2r69-qgv3-hr65
Record: https://patchnext.com/advisories/cve-2026-45245 (revision 3, source checked 26 Oct 2026, 12:52 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.6)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @steipete/summarize 0.15.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @steipete/summarize: affected < 0.15.1; fixed in 0.15.1

## Suggested inspection (read-only)
- `npm ls @steipete/summarize --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @steipete/summarize.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-2r69-qgv3-hr65 (OSV record GHSA-2r69-qgv3-hr65 lists affected ranges: npm @steipete/summarize >=0 <0.15.1 (fixed))
- Verified: https://github.com/advisories/GHSA-2r69-qgv3-hr65 (GitHub-reviewed advisory GHSA-2r69-qgv3-hr65 lists affected ranges: npm @steipete/summarize >=0 <0.15.1)

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