Cross-Site Scripting (XSS) in pyload-ng (CVE-2026-45348)
Summary
Cross-site scripting in pyload-ng (CVE-2026-45348). Confidential information can be exposed externally. Exploitable via POST /flash/add.
Original description
The description as published by the source.
Summary
The packages.js template at src/pyload/webui/app/themes/modern/templates/js/packages.js:172 interpolates a stored link URL into a template literal inside single-quoted HTML and then writes the result to the DOM via $(div).html(html). No escaping runs between the API value and innerHTML. An attacker (Alice) who can submit a package link puts a single quote plus event handler into the URL, breaks out of the attribute, and executes JavaScript in every operator's browser that opens the downloads view. The theme does not set a Content Security Policy that restricts inline script or event handlers.
Details
Sink: src/pyload/webui/app/themes/modern/templates/js/packages.js:165-188:
const html = `
${link.name}
${link.statusmsg} ${link.error}
${link.format_size}
${link.plugin}...
`;
const div = document.createElement("div");
$(div).attr("id", `file_${link.id}`);
$(div).css("padding-left", "30px");
$(div).css("cursor", "grab");
$(div).addClass("child");
$(div).html(html);
link.url flows in from /api/get_package_data, which returns the URL exactly as stored. Seven other fields on the same element (link.name, link.statusmsg, link.error, link.format_size, link.plugin, link.icon, link.id) share the same unescaped injection surface.
Source: src/pyload/core/api/__init__.py:541-600 (add_package) and the /api/add_package JSON route store the at…
Source: GitHub Security Advisories (Global) 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-2026-45348 has been found in pyload-ng.
Attackers can target a specific entry point like POST /flash/add over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 8.7/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "pyload-ng CVE-2026-45348" on the vendor's site.
CVE-2026-45348 (pyload-ng) — CWE-79 / CVSS v3 8.7
Attack vector: remote (network-reachable)
Attack surface: POST /flash/add / packages.js / innerHTML / link.url
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.
Cross-site scripting (XSS) (CWE-79) exists in pyload-ng. Attackers reach the vulnerable code path via POST /flash/add.
Check the vendor advisory for the affected versions of pyload-ng. Attack surface: POST /flash/add / packages.js / innerHTML / link.url.
Severity: High (CVSS 8.7/10). Confidential information can be exposed externally.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual POST /flash/add requests with malformed payloads or SQL meta-characters. Run grep -r 'pyload-ng' . 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 'pyload-ng' . | 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
pyload-ngを grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'POST /flash/add' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /flash/addへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Post-deployment verification verify
Replay attack against POST /flash/add on staging to confirm patch closes the vector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 Step 2 と同じログクエリでアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com