# CVE-2025-57539: CVE-2025-57539

Status: published. Published: 2025-09-09. Updated: 2026-11-08.

A stored cross-site scripting (XSS) vulnerability in the U2F Origin field of the Datacenter configuration in Proxmox Virtual Environment (PVE) 8.4 allows authenticated users to store malicious input. The payload is rendered unsafely in the Web UI and executed when viewed by other users, potentially leading to session hijacking or other attacks.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- proxmox / virtual_environment: 8.4 (affected, custom). Source: NVD

## NVD configuration conditions

Affected CPE matches depend on the following AND/OR and negation conditions:

```json
[
  {
    "negate": false,
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:proxmox:virtual_environment:8.4:*:*:*:*:*:*:*",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ],
    "operator": "OR"
  }
]
```

## Severity and prioritization

- CVSS 3.1: 5.4 (medium); CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N; source: NVD: 134c704f-9b21-4f2e-91b3-4a467353bcc0

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: exploitation poc; automatable no; technical impact partial; source NVD SSVC: 134c704f-9b21-4f2e-91b3-4a467353bcc0

- Weaknesses: CWE-79

## Exploit evidence

- exploit: https://github.com/khankishiyev-j/bug-bounty/blob/main/proxmox-xss (cve@mitre.org)
- exploit: https://github.com/khankishiyev-j/bug-bounty/blob/main/proxmox-xss (134c704f-9b21-4f2e-91b3-4a467353bcc0)

## References

- https://forum.proxmox.com/threads/proxmox-virtual-environment-security-advisories.149331/page-2#post-792010 (cve@mitre.org; Issue Tracking, Vendor Advisory)

- https://github.com/khankishiyev-j/bug-bounty/blob/main/proxmox-xss (cve@mitre.org; Exploit, Third Party Advisory)

- https://www.youtube.com/watch?v=-wvkN-7oT5U (cve@mitre.org; Broken Link)

- https://github.com/khankishiyev-j/bug-bounty/blob/main/proxmox-xss (134c704f-9b21-4f2e-91b3-4a467353bcc0; Exploit, Third Party Advisory)

## Provenance

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-57539; retrieved 2026-11-08; source updated 2026-11-08

Revision: 7b22b792c8f5ac86aa757098c18d50d74d809db00bf17ccec9891aba98bc4ee6

Canonical: https://y2.dev/cve/CVE-2025-57539

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.