Path Traversal in copyparty (CVE-2026-104102)
Summary
Path traversal in copyparty (CVE-2026-104102). Risk of unauthorized operations or information disclosure. Exploitable via ftp. Mitigation: upgrade to 1.20.19 or later.
Original description
The description as published by the source.
The FTP and FTPS server -- if enabled -- would allow uploading to any folder that the copyparty process had permission to write to.
The FTP-server is default-disabled, and must be explicitly enabled in the config with global-option ftp or ftps to be affected. Additionally, SFTP was not affected at all; only FTP and FTPS.
This was not a full read/write path-traversal; it had the following limitations:
- Only applied to uploads; it was not possible to read/download existing files in this manner.
- The output filename was not fully controllable; a randomized suffix would always be appended to the filename.
- Existing files could not be overwritten or appended to; only new files could be created.
- Filesystem-permissions would prevent writing to system folders, as copyparty surely does not run as root in most deployments.
- Copyparty itself will not execute arbitrary files as code by default, so this vulnerability could not be used to execute arbitrary code through copyparty.
The main concern is the potential effect on other unrelated software which is running on the same system.
The severity is assuming the worst case (SC:H/SI:H), that the same machine is running some unrelated software that will execute new arbitrarily-named files as code, and that the copyparty process has sufficient privileges to write files into the config-folder of that unrelated software.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-104102 has been found in copyparty.
Attackers can target a specific entry point like ftp over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade copyparty to 1.20.19 or later.
If unsure, ask your IT team or search "copyparty CVE-2026-104102" on the vendor's site.
CVE-2026-104102 (copyparty) — CWE-22
Attack surface: ftp / ftps
Patched: 1.20.19 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Path traversal (CWE-22) exists in copyparty. Attackers reach the vulnerable code path via ftp.
Check the vendor advisory for the affected versions of copyparty. Attack surface: ftp / ftps.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 1.20.19.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'copyparty' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'copyparty' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
copypartyを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade copyparty to 1.20.19ステージング環境で 1.20.19 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- web github.com
- web github.com
- web github.com
- web nvd.nist.gov
- web github.com