Information Disclosure in open-webui (CVE-2026-44557)
Summary
Vulnerability in open-webui (CVE-2026-44557). Risk of unauthorized operations or information disclosure. Exploitable via POST /query/doc. Mitigation: upgrade to 0.9.0 or later.
Original description
The description as published by the source.
Global Knowledge Base Enumeration via knowledge-bases Meta-Collection
Affected Component
Retrieval collection access validation:
backend/open_webui/routers/retrieval.py(lines 2330-2355,_validate_collection_access)backend/open_webui/routers/retrieval.py(query endpoints, e.g.POST /query/doc)
Affected Versions
Current main branch (commit 6fdd19bf1) and likely all versions with the knowledge base subsystem.
Description
The _validate_collection_access function uses an incomplete allowlist that only enforces ownership checks for collections matching user-memory-* and file-* patterns. All other collection names pass through unchecked — including the system-level knowledge-bases meta-collection, which stores the IDs, names, and descriptions of every knowledge base on the instance.
Any authenticated user can query this meta-collection directly via the retrieval query endpoints to obtain a global index of all knowledge bases across all users.
# retrieval.py:2330-2355 — incomplete collection allowlist
def _validate_collection_access(user, collection_name, ...):
if collection_name.startswith('user-memory-'):
# Check user-memory ownership
...
elif collection_name.startswith('file-'):
# Check file access
...
# Everything else (including "knowledge-bases") passes through unchecked
This finding is the enabler for the KB destruction (process/web), KB content injection (process/file), a…
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-2026-44557 has been found in open-webui.
Attackers can target a specific entry point like POST /query/doc 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 0.9.0 or later.
If unsure, ask your IT team or search "open-webui CVE-2026-44557" on the vendor's site.
CVE-2026-44557 (open-webui) — CWE-200 / CVSS v3 4.3
Attack vector: remote (network-reachable) / no user interaction
Attack surface: POST /query/doc / POST /api/v1/retrieval/query/doc / _validate_collection_access
Patched: 0.9.0 — 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.
Information disclosure (CWE-200) exists in open-webui. Attackers reach the vulnerable code path via POST /query/doc.
Check the vendor advisory for the affected versions of open-webui. Attack surface: POST /query/doc / POST /api/v1/retrieval/query/doc / _validate_collection_access.
Severity: Medium (CVSS 4.3/10). Risk of unauthorized operations or information disclosure.
Update to 0.9.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual POST /query/doc 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 /query/doc' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /query/doc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 0.9.0ステージング環境で 0.9.0 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 /query/doc 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