Unrestricted File Upload in Piwigo (CVE-2026-42322)
Summary
Vulnerability in Piwigo (CVE-2026-42322). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 16.4.0 or later.
Original description
The description as published by the source.
Piwigo is a full featured open source photo gallery application for the web. Prior to 16.4.0, admin/themes_standard_pages.php validates uploaded logo content by MIME type but reuses the attacker-controlled extension from std_pgs_logo when constructing the stored filename. An authenticated administrator can upload image content with a server-executable final extension, causing the file to be placed in the web-accessible logo directory and executed when requested if the web server handles that extension. This can permit arbitrary command execution, data disclosure, modification, persistence, and service disruption. This vulnerability is fixed in 16.4.0.
Source: NIST National Vulnerability Database NVD
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-2026-42322 has been found in Piwigo.
Successful exploitation can lead to full system takeover. CVSS score: 9.1/10.
What to do: upgrade Piwigo to 16.4.0 or later.
If unsure, ask your IT team or search "Piwigo CVE-2026-42322" on the vendor's site.
CVE-2026-42322 (Piwigo) — CWE-434 / CVSS v3 9.1
Attack vector: remote (network-reachable) / no user interaction
Patched: 16.4.0 — 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.
A vulnerability (CWE-434) exists in Piwigo.
Check the vendor advisory for the affected versions of Piwigo.
Severity: Critical (CVSS 9.1/10). Successful exploitation can lead to full system takeover.
Update to 16.4.0.
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 'Piwigo' . 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
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1Identify exposure identify
grep -r 'Piwigo' . | 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
Piwigo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 Piwigo to 16.4.0ステージング環境で 16.4.0 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。
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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。