Vulnerability in Desktop (CVE-2025-66549)
Summary
Vulnerability in Desktop (CVE-2025-66549). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 3.16.5 or later.
Original description
The description as published by the source.
Nextcloud Desktop is the desktop sync client for Nextcloud. Prior to 3.16.5, when trying to manually lock a file inside an end-to-end encrypted directory, the path of the file was sent to the server unencrypted, making it possible for administrators to see it in log files. This vulnerability is fixed in 3.16.5.
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-2025-66549 has been found in Desktop.
Risk of unauthorized operations or information disclosure. CVSS score: 2.4/10.
What to do: upgrade Desktop to 3.16.5 or later.
If unsure, ask your IT team or search "Desktop CVE-2025-66549" on the vendor's site.
CVE-2025-66549 (Desktop) — CWE-209 / CVSS v3 2.4
Attack vector: remote (network-reachable)
Patched: 3.16.5 — 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-209) exists in Desktop.
Check the vendor advisory for the affected versions of Desktop.
Severity: Low (CVSS 2.4/10). Risk of unauthorized operations or information disclosure.
Update to 3.16.5.
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 'Desktop' . 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 'Desktop' . | 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
Desktop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 Desktop to 3.16.5ステージング環境で 3.16.5 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。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2025-66549 nextcloud-desktop