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CVE-2026-43515
critical
CVSS 9.1
Vulnerability in tomcat (CVE-2026-43515)
Summary
vulnerability in tomcat (CVE-2026-43515). Confidential information can be exposed externally. Mitigation: upgrade to `10.1.55, 11.0.22, 9.0.118` or later.
AI summary snake-internal / snake-material-v2
A vulnerability tracked as **CVE-2026-43515** has been found in tomcat.
Confidential information can be exposed externally. CVSS score: 9.1/10.
What to do: upgrade tomcat to **10.1.55, 11.0.22, 9.0.118** or later.
If unsure, ask your IT team or search "tomcat CVE-2026-43515" on the vendor's site.
CVE-2026-43515 (tomcat) — CWE-285 / CVSS v3 9.1
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: `10.1.55, 11.0.22, 9.0.118` — 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** (CWE-285) exists in tomcat.
📍 Affected scope
tomcat — .
🔥 Severity
Severity: Critical (CVSS 9.1/10). Confidential information can be exposed externally
🔧 How to fix
Update to **10.1.55, 11.0.22, 9.0.118**.
🛡️ 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 'tomcat' .` 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 'tomcat' . | 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 `tomcat` 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 tomcat to 10.1.55, 11.0.22, 9.0.118ステージング環境で 10.1.55, 11.0.22, 9.0.118 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
Bitnami
tomcat
[{"type":"SEMVER","events":[{"introduced":"10.1.0"},{"fixed":"10.1.55"},{"introduced":"11.0.0"},{"fixed":"11.0.22"},{"introduced":"9.0.0"},{"fixed":"9.0.118"}]}]
maven
org.apache.tomcat.embed:tomcat-embed-core
[{"type":"ECOSYSTEM","events":[{"introduced":"11.0.0-M1"},{"fixed":"11.0.22"}]}]
maven
org.apache.tomcat:tomcat
[{"type":"ECOSYSTEM","events":[{"introduced":"11.0.0-M1"},{"fixed":"11.0.22"}]}]
maven
org.apache.tomcat:tomcat-catalina
[{"type":"ECOSYSTEM","events":[{"introduced":"11.0.0-M1"},{"fixed":"11.0.22"}]}]
References
- advisory https://nvd.nist.gov/vuln/detail/CVE-2026-43515
- package https://github.com/apache/tomcat
- web https://lists.apache.org/thread/746nxfxod0wsocxtmv8pb8nkgmwpc6bb
- web http://www.openwall.com/lists/oss-security/2026/05/12/11
- web https://github.com/advisories/GHSA-5m62-pw8w-7w9f
- web https://github.com/apache/tomcat/commit/276087d9c7abbcecc6c4fb4e4b08cf64780c6e36
- web https://github.com/apache/tomcat/commit/c621317382682206fb58ab92ebd3e1b6fdd10ce9
- web https://github.com/apache/tomcat/commit/db919ff9912b4d61d1b702a1342b8bde39270031
- web https://tomcat.apache.org/security-10.html
- web https://tomcat.apache.org/security-11.html
- web https://tomcat.apache.org/security-9.html