Vulnerability in typo3/cms-core (CVE-2021-21339)
Summary
Vulnerability in typo3/cms-core (CVE-2021-21339). Confidential information can be exposed externally. Mitigation: upgrade to 9.5.25 or later.
Original description
The description as published by the source.
Problem
User session identifiers were stored in cleartext - without processing of additional cryptographic hashing algorithms. This vulnerability cannot be exploited directly and occurs in combination with a chained attack - like for instance SQL injection in any other component of the system.
Solution
Update to TYPO3 versions 6.2.57, 7.6.51, 8.7.40, 9.5.25, 10.4.14, 11.1.1 that fix the problem described.
Credits
Thanks to TYPO3 security team member Oliver Hader who reported this issue and to TYPO3 core & security team members Benni Mack & Oliver Hader who fixed the issue.
References
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory 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 CVE-2021-21339 has been found in typo3/cms-core.
Confidential information can be exposed externally.
What to do: upgrade typo3/cms-core to 9.5.25 or later.
If unsure, ask your IT team or search "typo3/cms-core CVE-2021-21339" on the vendor's site.
CVE-2021-21339 (typo3/cms-core) — CWE-312
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 9.5.25 — 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 (CWE-312) exists in typo3/cms-core.
Check the vendor advisory for the affected versions of typo3/cms-core.
Severity: ?. Confidential information can be exposed externally.
Update to 9.5.25.
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 'typo3/cms-core' . 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
-
1Identify exposure identify
grep -r 'typo3/cms-core' . | 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
typo3/cms-core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 typo3/cms-core to 9.5.25ステージング環境で 9.5.25 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。
-
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 nvd.nist.gov
- web github.com
- web github.com
- web github.com
- web packagist.org
- web typo3.org