---
id: "CVE-2026-124556"
page: "https://infrastack.ai/live/CVE-2026-124556"
kind: "vulnerability"
aliases: ["CVE-2026-124556"]
title: "kkFileView: X-Base-Url header enables open redirect to attacker sites"
severity: "medium"
cvss: 5.0
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["java", "kkfileview", "package", "self-hosted"]
not_affected_if: ["header-stripped-at-proxy"]
published_at: "2026-11-09T03:16:37+00:00"
first_seen_at: "2026-11-09T03:24:19+00:00"
updated_at: "2026-11-09T03:26:28+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-124556", "first_seen_at": "2026-11-09T03:24:19+00:00"}]
exploit_sources: []
---

# kkFileView: X-Base-Url header enables open redirect to attacker sites

Link for people: https://infrastack.ai/live/CVE-2026-124556 (this .md is for agents)

kkFileView, a Java file preview server, trusts the X-Base-Url request header when building base URLs in BaseUrlFilter.getBaseUrl. An attacker can make the server redirect users to an arbitrary external site, which supports phishing.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the deployed kkFileView version against `5.0.3`; versions up to and including `5.0.3` are reported as affected.
- Look for `BaseUrlFilter.java` under `server/src/main/java/cn/keking/web/filter/` in the source or build to confirm the code path is present.
- Send a request with an `X-Base-Url` header set to an external host and see whether redirect responses point there.

## Timeline

- 2026-11-09T03:24:19+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-124556

## Documents

- [advisory] Vendor advisory: github.com https://github.com/kekingcn/kkFileView/security/advisories/GHSA-wrm9-r4fj-f8q5

## From the sources

A security vulnerability has been detected in kekingcn kkFileView up to 5.0.3. This issue affects the function BaseUrlFilter.getBaseUrl of the file server/src/main/java/cn/keking/web/filter/BaseUrlFilter.java. The manipulation of the argument X-Base-Url leads to open redirect. The attack is possible to be carried out remotely. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

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_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_