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UBUNTU-CVE-2026-25953
Vulnerability in freerdp (UBUNTU-CVE-2026-25953)
Summary
vulnerability in freerdp (UBUNTU-CVE-2026-25953). Successful exploitation can lead to full system takeover. Exploitable via ``xf_AppUpdateWindowFromSurface``. Mitigation: upgrade to `3.5.1+dfsg1-0ubuntu1.4` or later.
AI summary snake-internal / snake-material-v2
A vulnerability tracked as **UBUNTU-CVE-2026-25953** has been found in freerdp.
Attackers can target a specific entry point like ``xf_AppUpdateWindowFromSurface`` over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: ?/10.
What to do: upgrade freerdp to **3.5.1+dfsg1-0ubuntu1.4** or later.
If unsure, ask your IT team or search "freerdp UBUNTU-CVE-2026-25953" on the vendor's site.
UBUNTU-CVE-2026-25953 (freerdp) —
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: `xf_AppUpdateWindowFromSurface` / `xfAppWindow` / `xf_rail_get_window`
Patched: `3.5.1+dfsg1-0ubuntu1.4` — 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.
❓ What is the problem
**A vulnerability** (unclassified) exists in freerdp. Attackers reach the vulnerable code path via ``xf_AppUpdateWindowFromSurface`` without authentication.
📍 Affected scope
freerdp — . Attack surface: `xf_AppUpdateWindowFromSurface` / `xfAppWindow` / `xf_rail_get_window`.
🔥 Severity
Severity: ?. Successful exploitation can lead to full system takeover
🔧 How to fix
Update to **3.5.1+dfsg1-0ubuntu1.4**.
🛡️ Workaround
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
🔍 Detection
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run `grep -r 'freerdp' .` against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response Actions (7 steps)
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'freerdp' . | 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 `freerdp` を grep し、稼働しているサービス・バージョンを把握する。
-
6Apply patch patch
Upgrade freerdp to 3.5.1+dfsg1-0ubuntu1.4ステージング環境で 3.5.1+dfsg1-0ubuntu1.4 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と、Step 3 で見つけた異常検知の続報チェックを含めること。
-
7Post-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 Step 3 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
Ubuntu:16.04:LTS
freerdp
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:Pro:18.04:LTS
freerdp2
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:18.04:LTS
freerdp
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:Pro:20.04:LTS
freerdp2
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:22.04:LTS
freerdp2
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:24.04:LTS
freerdp3
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.5.1+dfsg1-0ubuntu1.4"}]}]
Ubuntu:Pro:24.04:LTS
freerdp2
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:25.10
freerdp3
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.16.0+dfsg-2ubuntu0.3"}]}]
References
- advisory https://ubuntu.com/security/notices/USN-8105-1
- report https://ubuntu.com/security/CVE-2026-25953
- report https://www.cve.org/CVERecord?id=CVE-2026-25953
- report https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-p6rq-rxpc-rh3p
- report https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L1230-L1237
- report https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L257-L290
- report https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_rail.c#L643-L647
- report https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_window.c#L1394-L1428
- report https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_window.c#L1462-L1470
- report https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/client/X11/xf_window.c#L1484-L1491
- report https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/libfreerdp/gdi/gfx.c#L254-L286
- report https://github.com/FreeRDP/FreeRDP/blob/5c7aae27d0417b42b4806c2a5c583ca39dd9ef1e/libfreerdp/gdi/gfx.c#L278-L279