Vulnerability in modsecurity (CVE-2026-42268)
Summary
Vulnerability in modsecurity (CVE-2026-42268). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 3.0.15 or later.
Original description
The description as published by the source.
ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. From 3.0.0 to before 3.0.15, there is an unhandled exception (std::out_of_range) caused by unsigned integer underflow in libmodsecurity3 if the user (administrator) uses a rule any of @verifySSN, @verifyCPF, or @verifySVNR. This vulnerability is fixed in 3.0.15.
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-2026-42268 has been found in modsecurity.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: upgrade modsecurity to 3.0.15 or later.
If unsure, ask your IT team or search "modsecurity CVE-2026-42268" on the vendor's site.
CVE-2026-42268 (modsecurity) — CWE-191 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 3.0.15 — 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-191) exists in modsecurity.
Check the vendor advisory for the affected versions of modsecurity.
Severity: High (CVSS 7.5/10). Risk of unauthorized operations or information disclosure.
Update to 3.0.15.
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 'modsecurity' . 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 'modsecurity' . | 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
modsecurity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 modsecurity to 3.0.15ステージング環境で 3.0.15 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
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-42268 modsecurity
- Ubuntu UBUNTU-CVE-2026-42268 modsecurity
References
- advisory github.com
- web nvd.nist.gov