Vulnerability in open-webui (CVE-2026-54006)
Summary
Vulnerability in open-webui (CVE-2026-54006). Risk of unauthorized operations or information disclosure. Exploitable via POST /api/v1/calendars/events/{event_id}/update. Mitigation: upgrade to 0.9.6 or later.
Original description
The description as published by the source.
Summary
POST /api/v1/calendars/events/{event_id}/update validates that the caller has write access to the calendar the event currently belongs to, but does not validate the destination calendar_id supplied in the request body. The model layer then persists the new calendar_id unconditionally.
A regular user-role account can therefore create an event in their own calendar and immediately move it into any other user's calendar whose ID they know — bypassing the authorization check that create_event correctly performs. This is reachable on default configuration: ENABLE_CALENDAR and USER_PERMISSIONS_FEATURES_CALENDAR both default to True.
Details
Sink — missing destination check
backend/open_webui/routers/calendar.py:283-297
@router.post('/events/{event_id}/update', response_model=CalendarEventModel)
async def update_event(
request: Request, event_id: str, form_data: CalendarEventUpdateForm,
user: UserModel = Depends(get_verified_user)
):
await check_calendar_permission(request, user)
event = await CalendarEvents.get_event_by_id(event_id)
if not event:
raise HTTPException(status_code=404, detail='Event not found')
await _check_calendar_access(event.calendar_id, user, 'write') # ← SOURCE only
updated = await CalendarEvents.update_event_by_id(event_id, form_data) # ← writes form_data.calendar_id
...
backend/open_webui/models/calendar.py:658-693 (update_event_by_id)
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-2026-54006 has been found in open-webui.
Attackers can target a specific entry point like POST /api/v1/calendars/events/{event_id}/update over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 4.3/10.
What to do: upgrade open-webui to 0.9.6 or later.
If unsure, ask your IT team or search "open-webui CVE-2026-54006" on the vendor's site.
CVE-2026-54006 (open-webui) — CWE-639 / CVSS v3 4.3
Attack vector: remote (network-reachable) / no user interaction
Attack surface: POST /api/v1/calendars/events/{event_id}/update / POST /api/v1/auths/add / GET /api/v1/calendars/ / GET /events/{id}
Patched: 0.9.6 — 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-639) exists in open-webui. Attackers reach the vulnerable code path via POST /api/v1/calendars/events/{event_id}/update.
Check the vendor advisory for the affected versions of open-webui. Attack surface: POST /api/v1/calendars/events/{event_id}/update / POST /api/v1/auths/add / GET /api/v1/calendars/ / GET /events/{id}.
Severity: Medium (CVSS 4.3/10). Risk of unauthorized operations or information disclosure.
Update to 0.9.6.
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 /api/v1/calendars/events/{event_id}/update requests with malformed payloads or SQL meta-characters. Run grep -r 'open-webui' . 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 'open-webui' . | 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
open-webui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 /api/v1/calendars/events/{event_id}/update' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /api/v1/calendars/events/{event_id}/update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。 -
3Apply patch patch
Upgrade open-webui to 0.9.6ステージング環境で 0.9.6 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 2 で見つけた異常検知の続報チェックを含めること。
-
4Post-deployment verification verify
Replay attack against POST /api/v1/calendars/events/{event_id}/update 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 github.com
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com
- web pypi.org