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UBUNTU-CVE-2026-53404

Vulnerability in tomcat6 (UBUNTU-CVE-2026-53404)

Summary

Vulnerability in tomcat6 (UBUNTU-CVE-2026-53404). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 8.0.32-1ubuntu1.13+esm2 or later.

Original description

The description as published by the source.

Always-Incorrect Control Flow Implementation vulnerability in Apache Tomcat's rewrite valve meant that if the first condition in an OR chain matched, subsequent non-OR conditions were skipped. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100. Other versions that have reached end of support may also be affected. Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119, which fix the issue.

Source: OSV.dev (Open Source Vulnerabilities) OSV

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 UBUNTU-CVE-2026-53404 has been found in tomcat6.
Risk of unauthorized operations or information disclosure.
What to do: upgrade tomcat6 to 8.0.32-1ubuntu1.13+esm2 or later.
If unsure, ask your IT team or search "tomcat6 UBUNTU-CVE-2026-53404" on the vendor's site.

UBUNTU-CVE-2026-53404 (tomcat6)
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 8.0.32-1ubuntu1.13+esm2 — 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 tomcat6.

📍 Affected scope

Check the vendor advisory for the affected versions of tomcat6.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 8.0.32-1ubuntu1.13+esm2.

🛡️ 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 'tomcat6' . 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

1
Identify exposure identify
```
grep -r 'tomcat6' . | 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 tomcat6 を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade tomcat6 to 8.0.32-1ubuntu1.13+esm2
```
ステージング環境で 8.0.32-1ubuntu1.13+esm2 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を含めること。
3
Post-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。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。