Cross-Site Scripting (XSS) in getkirby/cms (CVE-2026-54002)
Summary
Cross-site scripting in getkirby/cms (CVE-2026-54002). Risk of unauthorized operations or information disclosure. Exploitable via writer. Mitigation: upgrade to 5.4.4 or later.
Original description
The description as published by the source.
Kirby is an open-source content management system. Prior to 4.9.4 and 5.4.4, Kirby sites and plugins that use the writer or list fields or call Dom::sanitize(), Sane::sanitize(), Sane::Html::sanitize(), Sane::Svg::sanitize(), Sane::Xml::sanitize(), Sane::sanitizeFile(), or file sanitizeContents() with untrusted input allow malicious markup injected as children of an unknown HTML or XML tag to pass through Dom::sanitize() without being correctly sanitized, causing stored cross-site scripting. This issue is fixed in versions 4.9.4 and 5.4.4.
Source: GitHub Security Advisories (Global) 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-2026-54002 has been found in getkirby/cms.
Attackers can target a specific entry point like writer over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade getkirby/cms to 5.4.4 or later.
If unsure, ask your IT team or search "getkirby/cms CVE-2026-54002" on the vendor's site.
CVE-2026-54002 (getkirby/cms) — CWE-79
Attack surface: writer / list / Sane
Patched: 5.4.4 — 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 getkirby/cms. Attackers reach the vulnerable code path via writer.
Check the vendor advisory for the affected versions of getkirby/cms. Attack surface: writer / list / Sane.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 5.4.4.
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 'getkirby/cms' . 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 'getkirby/cms' . | 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
getkirby/cms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 getkirby/cms to 5.4.4ステージング環境で 5.4.4 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 github.com
- advisory github.com
- advisory nvd.nist.gov
- package github.com
- patch github.com
- patch github.com
- patch github.com
- patch github.com
- web github.com
- web github.com
- web github.com