Cross-Site Scripting (XSS) in mautic/core (CVE-2021-27912)
Summary
Cross-site scripting in mautic/core (CVE-2021-27912). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 4.0.0 or later.
Original description
The description as published by the source.
Mautic versions before 3.3.4/4.0.0 are vulnerable to an inline JS XSS attack when viewing Mautic assets by utilizing inline JS in the title and adding a broken image URL as a remote asset. This can only be leveraged by an authenticated user with permission to create or edit assets.
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-2021-27912 has been found in mautic/core.
Risk of unauthorized operations or information disclosure.
What to do: upgrade mautic/core to 4.0.0 or later.
If unsure, ask your IT team or search "mautic/core CVE-2021-27912" on the vendor's site.
CVE-2021-27912 (mautic/core) — CWE-79
Attack vector: remote (network-reachable)
Patched: 4.0.0 — 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.
Cross-site scripting (XSS) (CWE-79) exists in mautic/core.
Check the vendor advisory for the affected versions of mautic/core.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 4.0.0.
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 'mautic/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 'mautic/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
mautic/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 mautic/core to 4.0.0ステージング環境で 4.0.0 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
- package github.com
- patch github.com
- web github.com