How severe is GHSA-c8x8-7fp4-3x9w?

No CVSS score has been assigned to GHSA-c8x8-7fp4-3x9w yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-c8x8-7fp4-3x9w?

GHSA-c8x8-7fp4-3x9w affects the following packages: prosemirror-view (npm). Ecosystems affected: npm.

How do I fix GHSA-c8x8-7fp4-3x9w?

Update prosemirror-view to 1.42.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-c8x8-7fp4-3x9w is resolved across your whole dependency graph.

How do I detect GHSA-c8x8-7fp4-3x9w in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for prosemirror-view, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-c8x8-7fp4-3x9w if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is GHSA-c8x8-7fp4-3x9w actively exploited in the wild?

No public exploit code has been indexed for GHSA-c8x8-7fp4-3x9w yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-c8x8-7fp4-3x9w?

GHSA-c8x8-7fp4-3x9w has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 22th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-c8x8-7fp4-3x9w?

GHSA-c8x8-7fp4-3x9w is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was GHSA-c8x8-7fp4-3x9w published, and has it been updated?

GHSA-c8x8-7fp4-3x9w was published on October 5, 2026 and was last updated on October 5, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

Not in CISA KEV

ProseMirror has a XSS vulnerability in prosemirror-view's paste handlingGHSA-c8x8-7fp4-3x9w

Fix: ProseMirror/prosemirror-view@20dc0a9

GHSA-c8x8-7fp4-3x9w is a Cross-site Scripting (XSS) vulnerability in prosemirror-view. A fix is available for prosemirror-view — see the affected versions and patch details below.

Also known asCVE-2026-104847

Published

Oct 5, 2026

Updated

Oct 5, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

A successful exploit gives an attacker total control of the affected component, not partial access.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-c8x8-7fp4-3x9w.

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs22th percentile — riskier than 22% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

1Kother npm packages depend on this — each one inherits the vulnerability until it's patched upstream

prosemirror-viewnpm

16.7Mdownloads / week

Description

ProseMirror's view component renders and manages the editable browser interface for ProseMirror documents. Prior to 1.42.3, prosemirror-view paste handling accepts attacker-provided HTML whose clipboard slice context contains attributes that are not passed through schema attribute validation. When a user pastes the crafted HTML into an editor, the unvalidated context attributes can construct content that executes attacker-controlled JavaScript in the browser window containing the editor. This issue is fixed in version 1.42.3.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`prosemirror-view`	all versions	1.42.3`npm install prosemirror-view@1.42.3`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for prosemirror-view, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update prosemirror-view to 1.42.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-c8x8-7fp4-3x9w is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Frequently Asked Questions

### Impact When a user pastes attacker-provided HTML into a ProseMirror editor component, this can cause attacker-controlled JavaScript code to run in the browser window containing the editor. ### Patches Version 1.42.3 adds validation that prevents this attack. ### Workarounds No known workarounds.

O3 Security · Impact-Aware SCA

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