CVE-2026-104847

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.

References

• https://github.com/ProseMirror/prosemirror-view/commit/20dc0a911a79f8fc6640dbbea5e7d68d3c4784b7
• https://github.com/ProseMirror/prosemirror-view/commit/2e91a612bbc1248e55b4f6061fc93fe459f977c1
• https://github.com/ProseMirror/prosemirror-view/security/advisories/GHSA-c8x8-7fp4-3x9w
• https://github.com/ProseMirror/prosemirror-view/security/advisories/GHSA-c8x8-7fp4-3x9w
• https://github.com/ProseMirror/prosemirror-view/security/advisories/GHSA-c8x8-7fp4-3x9w
• https://github.com/ProseMirror/prosemirror-view/security/advisories/GHSA-c8x8-7fp4-3x9w