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UBUNTU-CVE-2020-11996
Vulnerability in tomcat8 (UBUNTU-CVE-2020-11996)
Summary
vulnerability in tomcat8 (UBUNTU-CVE-2020-11996). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to `9.0.31-1ubuntu0.1` or later.
AI summary snake-internal / snake-material-v2
A vulnerability tracked as **UBUNTU-CVE-2020-11996** has been found in tomcat8.
Risk of unauthorized operations or information disclosure. CVSS score: ?/10.
What to do: upgrade tomcat8 to **9.0.31-1ubuntu0.1** or later.
If unsure, ask your IT team or search "tomcat8 UBUNTU-CVE-2020-11996" on the vendor's site.
UBUNTU-CVE-2020-11996 (tomcat8) —
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: `9.0.31-1ubuntu0.1` — 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 tomcat8.
📍 Affected scope
tomcat8 — .
🔥 Severity
Severity: ?. Risk of unauthorized operations or information disclosure
🔧 How to fix
Update to **9.0.31-1ubuntu0.1**.
🛡️ 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 'tomcat8' .` 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 'tomcat8' . | 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 `tomcat8` 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 tomcat8 to 9.0.31-1ubuntu0.1ステージング環境で 9.0.31-1ubuntu0.1 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:Pro:18.04:LTS
tomcat8
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:Pro:18.04:LTS
tomcat9
[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]
Ubuntu:20.04:LTS
tomcat9
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.0.31-1ubuntu0.1"}]}]
References
- advisory https://ubuntu.com/security/notices/USN-4596-1
- report https://ubuntu.com/security/CVE-2020-11996
- report https://www.openwall.com/lists/oss-security/2020/06/25/6
- report https://github.com/apache/tomcat/commit/9a0231683a77e2957cea0fdee88b193b30b0c976
- report https://github.com/apache/tomcat/commit/c8acd2ab7371e39aeca7c306f3b5380f00afe552
- report https://lists.apache.org/thread.html/r5541ef6b6b68b49f76fc4c45695940116da2bcbe0312ef204a00a2e0%40%3Cannounce.tomcat.apache.org%3E
- report https://lists.apache.org/thread.html/r74f5a8204efe574cbfcd95b2a16236fe95beb45c4d9fee3dc789dca9@%3Ccommits.ofbiz.apache.org%3E
- report https://lists.apache.org/thread.html/r8f3d416c193bc9384a8a7dd368623d441f5fcaff1057115008100561@%3Ccommits.ofbiz.apache.org%3E
- report https://lists.apache.org/thread.html/r8f7484589454638af527182ae55ef5b628ba00c05c5b11887c922fb1@%3Cnotifications.ofbiz.apache.org%3E
- report https://lists.apache.org/thread.html/r93ca628ef3a4530dfe5ac49fddc795f0920a4b2a408b57a30926a42b@%3Ccommits.ofbiz.apache.org%3E
- report https://lists.apache.org/thread.html/ra7092f7492569b39b04ec0decf52628ba86c51f15efb38f5853e2760@%3Cnotifications.ofbiz.apache.org%3E
- report https://lists.apache.org/thread.html/rb4ee49ecc4c59620ffd5e66e84a17e526c2c3cfa95d0cd682d90d338@%3Cnotifications.ofbiz.apache.org%3E
- report https://lists.apache.org/thread.html/rb820f1a2a02bf07414be12c653c2ab5321fd87b9bf6c5e635c53ff4b@%3Cnotifications.ofbiz.apache.org%3E
- report https://lists.apache.org/thread.html/rc80b96b4b96618b2b7461cb90664a428cfd6605eea9f74e51b792542@%3Cnotifications.ofbiz.apache.org%3E
- report https://lists.apache.org/thread.html/rea65d6ef2e45dd1c45faae83922042732866c7b88fa109b76c83db52@%3Cnotifications.ofbiz.apache.org%3E
- report https://www.cve.org/CVERecord?id=CVE-2020-11996