---
id: "CVE-2021-48013"
kind: "vulnerability"
aliases: ["CVE-2021-48013"]
title: "Weaver E-cology 8.0: unauthenticated path traversal reads arbitrary server files"
severity: "high"
cvss: 8.7
epss: 0.00736
exploited: true
status: "open"
category: "other"
products: [{"name": "E-cology", "fixed": [], "affected": "8.0", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["java", "other", "path-traversal", "self-hosted", "weaver-e-cology"]
not_affected_if: ["managed-hosting"]
published_at: "2026-10-22T11:17:04+00:00"
first_seen_at: "2026-10-23T21:57:30+00:00"
updated_at: "2026-10-24T07:15:51+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-48013", "first_seen_at": "2026-10-23T21:57:30+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-10-23T23:43:01+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2021-48013", "first_seen_at": "2026-10-24T07:15:51+00:00"}]
---

# Weaver E-cology 8.0: unauthenticated path traversal reads arbitrary server files

Weaver E-cology 8.0 lets anyone without a login read arbitrary files through the fpath parameter of /weaver/ln.FileDownload, for example WEB-INF/web.xml and weaver.properties (database credentials). Exploitation was observed by Shadowserver on 2023-10-18, and public PoCs and nuclei templates exist. No vendor fix or fixed version is published.

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

## Affected

- vendor:E-cology affected 8.0 fixed ?

## How to check

Safe read-only test on your own instance: GET /weaver/ln.FileDownload?fpath=../ecology/WEB-INF/web.xml. A 200 response whose body contains <url-pattern>/weaver/ means vulnerable (the public nuclei template uses this match). Also check whether /weaver/ is reachable from the internet.

## Fix

No fixed version published by Weaver as of 2026-10-23. Ask Weaver for the latest patch. Until then, block /weaver/ln.FileDownload at the WAF or reverse proxy, remove internet exposure of E-cology, and rotate credentials in WEB-INF/prop/weaver.properties if the endpoint was reachable.

## Timeline

- 2026-10-23T21:57:30+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2021-48013
- 2026-10-23T23:43:01+00:00 analyst — No vendor advisory or fixed version found (VulnCheck, IONIX, NVD all say none); public PoC/nuclei template since 2021-2023 (cnblogs); Shadowserver saw exploitation 2023-10-18; not in CISA KEV, EPSS 0.74%. Exploited flag set from CVE record's Shadowserver observation.
- 2026-10-24T07:15:51+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2021-48013

## Documents

- [advisory] VulnCheck: Weaver E-cology 8.0 path traversal via ln.FileDownload https://www.vulncheck.com/advisories/weaver-e-cology-8.0-unauthenticated-path-traversal-via-ln-filedownload
- [describes] IONIX: CVE-2021-48013 https://www.ionix.io/threat-center/cve-2021-48013/
- [poc] E-cology filedownload traversal PoC and nuclei template (2023-09-04) https://www.cnblogs.com/pursue-security/p/17677229.html

## From the sources

Weaver E-cology 8.0 contains a path traversal vulnerability that allows unauthenticated attackers to read arbitrary files through the fpath parameter of the /weaver/ln.FileDownload endpoint. Attackers can send crafted GET requests with directory traversal sequences in fpath to retrieve sensitive files such as WEB-INF/web.xml from the server. Exploitation evidence was first observed by the Shadowserver Foundation on 2023-10-18.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_