---
id: CVE-2026-88592
title: kkFileView >= 4.2.0 is vulnerable to Server-Side Request Forgery (SSRF)
summary: >-
  kkFileView >= 4.2.0 is vulnerable to Server-Side Request Forgery (SSRF). The
  cross-origin file proxy endpoint /getCorsFile is protected by TrustHostFilter
  against the trust.host whitelist. However, the URL parameter validated by the
  filt…
severity: critical
cvss: 9.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-345
published: '2026-09-16'
updated: '2026-09-22'
sourceUpdated: '2026-09-22T20:00:03.713'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-88592'
references:
  - url: 'https://github.com/sg-summer/cve/issues/2'
    label: cve@mitre.org
  - url: 'https://github.com/sg-summer/cve/issues/2'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
epss: 0.00211
epssPercentile: 0.10148
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-09-17T19:33:08.117968Z'
ingestedAt: '2026-09-16T20:03:30.762Z'
---

## Overview

kkFileView >= 4.2.0 is vulnerable to Server-Side Request Forgery (SSRF). The cross-origin file proxy endpoint /getCorsFile is protected by TrustHostFilter against the trust.host whitelist. However, the URL parameter validated by the filter is not the same parameter the controller actually fetches: the filter validates the first non-empty parameter in a fixed priority order, while the controller only reads and fetches urlPath. By supplying both urlPath=<real target> and url=<whitelisted decoy address> in the same request, the decoy passes validation while the unvalidated real target is fetched server-side — and the response body is echoed back to the attacker.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.