CVE-2026-56672
Stored XSS in ComfyUI /userdata endpoint allows theft of browser tokens and authenticated API access.
Is CVE-2026-56672 being exploited?
Not confirmed. CVE-2026-56672 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.24% probability of exploitation in the next 30 days.
How severe is CVE-2026-56672?
CVE-2026-56672 is rated High with a CVSS score of 8.2. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-56672?
Yes. A fix has been recorded for CVE-2026-56672. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-56672 affect?
CVE-2026-56672 affects ComfyUI < 0.28.0, Self-hosted ComfyUI servers exposing /userdata endpoint, Instances allowing user file uploads. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-56672?
Upgrade to ComfyUI >= 0.28.0; restrict/sanitize uploads; block /userdata GETs until patched.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Stored XSS executes attacker HTML/SVG in ComfyUI origin, enabling theft of browser-stored API tokens, settings, workflows and authenticated-equivalent API calls.
Patch when possible
- affected< 0.28.0
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.