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CVE-2026-40072
high
CVSS 7.2
SSRF (Server-Side Request Forgery) in web3 (CVE-2026-40072)
Summary
SSRF in web3 (CVE-2026-40072). Risk of unauthorized operations or information disclosure. Exploitable via ``OffchainLookup``. Mitigation: upgrade to `8.0.0b2` or later.
AI summary snake-internal / snake-material-v2
A vulnerability tracked as **CVE-2026-40072** has been found in web3.
Attackers can target a specific entry point like ``OffchainLookup`` over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 7.2/10.
What to do: upgrade web3 to **8.0.0b2** or later.
If unsure, ask your IT team or search "web3 CVE-2026-40072" on the vendor's site.
CVE-2026-40072 (web3) — CWE-918 / CVSS v3 7.2
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: `OffchainLookup` / `requests` / `aiohttp` / `eth_call`
Patched: `8.0.0b2` — 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
**SSRF** (CWE-918) exists in web3. Attackers reach the vulnerable code path via ``OffchainLookup`` without authentication.
📍 Affected scope
web3 — . Attack surface: `OffchainLookup` / `requests` / `aiohttp` / `eth_call`.
🔥 Severity
Severity: High (CVSS 7.2/10). Risk of unauthorized operations or information disclosure
🔧 How to fix
Update to **8.0.0b2**.
🛡️ 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 'web3' .` 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
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1Identify exposure identify
grep -r 'web3' . | 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 `web3` を grep し、稼働しているサービス・バージョンを把握する。
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6Apply patch patch
Upgrade web3 to 8.0.0b2ステージング環境で 8.0.0b2 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。
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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
pip
web3
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.0.0b2"}]}]
PyPI
web3
[{"type":"ECOSYSTEM","events":[{"introduced":"8.0.0b1"},{"fixed":"8.0.0b2"}]}]
References
- advisory https://nvd.nist.gov/vuln/detail/CVE-2026-40072
- package https://github.com/ethereum/web3.py
- web https://github.com/ethereum/web3.py/commit/b1c57bb0a124359c9902daaefab4d8af7c3c4c1e
- web https://github.com/ethereum/web3.py/security/advisories/GHSA-5hr4-253g-cpx2
- web https://github.com/advisories/GHSA-5hr4-253g-cpx2