Vulnerability in Apache (CVE-2026-100669)
Summary
Vulnerability in Apache (CVE-2026-100669). Confidential information can be exposed externally. Exploitable via GET /user/CONFIG/system.YAML. Mitigation: upgrade to 2.0.25 or later.
Original description
The description as published by the source.
Grav before 2.0.25 ships web server configuration samples whose access-control deny rules are matched case-sensitively. In webserver-configs/web.config (IIS), every deny rule (user_sensitive_folders, user_accounts, user_data, user_error_redirect, user_pages, system, vendor, ignore_folders) sets ignoreCase="false" on its URL Rewrite element, overriding the IIS default of ignoreCase="true"; because these are rewrite matches rather than elements, there is no case-insensitive fallback. On IIS running over case-insensitive NTFS, an unauthenticated remote attacker can vary the case of a folder name or file extension (for example GET /user/CONFIG/system.YAML) so that no deny rule matches and the IIS static file handler resolves and returns the underlying file, disclosing sensitive data such as configuration secrets or account password hashes. Whether a bypassed file is actually returned depends on MIME registration: .json is served by default, while .yaml/.yml return HTTP 404.3 on a stock IIS unless a YAML MIME mapping has been added. The same class of gap exists in the bundled webserver-configs/lighttpd.conf, whose user/(config|env), directory, script-extension, root-file and dotfile rules lack the (?i) modifier, though it is lower risk because lighttpd typically runs on case-sensitive filesystems. Deployments served by Apache (.htaccess), nginx, Caddy, or the PHP built-in server are not affected. The issue is fixed in 2.0.25; because the .htaccess installer heal does not touch w…
Source: NIST National Vulnerability Database NVD GitHub Advisory
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-2026-100669 has been found in Apache.
Attackers can target a specific entry point like GET /user/CONFIG/system.YAML over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 7.5/10.
What to do: upgrade Apache to 2.0.25 or later.
If unsure, ask your IT team or search "Apache CVE-2026-100669" on the vendor's site.
CVE-2026-100669 (Apache) — CWE-178 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: GET /user/CONFIG/system.YAML
Patched: 2.0.25 — 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-178) exists in Apache. Attackers reach the vulnerable code path via GET /user/CONFIG/system.YAML without authentication.
Check the vendor advisory for the affected versions of Apache. Attack surface: GET /user/CONFIG/system.YAML.
Severity: High (CVSS 7.5/10). Confidential information can be exposed externally.
Update to 2.0.25.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual GET /user/CONFIG/system.YAML requests with malformed payloads or SQL meta-characters. Run grep -r 'Apache' . 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 'Apache' . | 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
Apacheを grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'GET /user/CONFIG/system.YAML' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
GET /user/CONFIG/system.YAMLへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Apply patch patch
Upgrade Apache to 2.0.25ステージング環境で 2.0.25 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と、Step 2 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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4Post-deployment verification verify
Replay attack against GET /user/CONFIG/system.YAML on staging to confirm patch closes the vector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 2 と同じログクエリでアラート再発が無いか継続監視。
References
- web github.com
- web vulncheck.com
- web nvd.nist.gov
- web github.com