Vulnerability in tomcat9 (UBUNTU-CVE-2020-17527)
Summary
Vulnerability in tomcat9 (UBUNTU-CVE-2020-17527). Confidential information can be exposed externally. Mitigation: upgrade to 9.0.16-3ubuntu0.18.04.2 or later.
Original description
The description as published by the source.
While investigating bug 64830 it was discovered that Apache Tomcat 10.0.0-M1 to 10.0.0-M9, 9.0.0-M1 to 9.0.39 and 8.5.0 to 8.5.59 could re-use an HTTP request header value from the previous stream received on an HTTP/2 connection for the request associated with the subsequent stream. While this would most likely lead to an error and the closure of the HTTP/2 connection, it is possible that information could leak between requests.
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-2020-17527 has been found in tomcat9.
Confidential information can be exposed externally.
What to do: upgrade tomcat9 to 9.0.16-3ubuntu0.18.04.2 or later.
If unsure, ask your IT team or search "tomcat9 UBUNTU-CVE-2020-17527" on the vendor's site.
UBUNTU-CVE-2020-17527 (tomcat9)
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 9.0.16-3ubuntu0.18.04.2 — 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.
A vulnerability (unclassified) exists in tomcat9.
Check the vendor advisory for the affected versions of tomcat9.
Severity: ?. Confidential information can be exposed externally.
Update to 9.0.16-3ubuntu0.18.04.2.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'tomcat9' . 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
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1Identify exposure identify
grep -r 'tomcat9' . | 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
tomcat9を grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade tomcat9 to 9.0.16-3ubuntu0.18.04.2ステージング環境で 9.0.16-3ubuntu0.18.04.2 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。
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3Post-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。
Affected packages
References
- advisory ubuntu.com
- report ubuntu.com
- report github.com
- report github.com
- report openwall.com
- report lists.apache.org
- report lists.apache.org
- report lists.apache.org
- report lists.apache.org
- report lists.apache.org
- report lists.apache.org
- report cve.org