Vulnerability in dompurify (CVE-2026-65902)
Summary
Vulnerability in dompurify (CVE-2026-65902). Risk of unauthorized operations or information disclosure. Exploitable via data.allowedTags. Mitigation: upgrade to 3.4.7 or later.
Original description
The description as published by the source.
DOMPurify before 3.4.7 (affected versions <= 3.4.5) passes direct references to the module-level DEFAULT_ALLOWED_TAGS and DEFAULT_ALLOWED_ATTR sets to the uponSanitizeElement and uponSanitizeAttribute hooks via data.allowedTags / data.allowedAttributes when sanitize is called without an explicit cfg.ALLOWED_TAGS / cfg.ALLOWED_ATTR array. A hook that mutates these fields permanently widens the default allow-lists for the lifetime of the DOMPurify instance, so all subsequent default-config sanitize calls inherit the widened defaults and attacker payloads using the poisoned tag/attribute name survive sanitization. removeAllHooks(), clearConfig(), and passing a fresh cfg do not recover the state; only constructing a new DOMPurify instance does.
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-2026-65902 has been found in dompurify.
Attackers can target a specific entry point like data.allowedTags over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 6.1/10.
What to do: upgrade dompurify to 3.4.7 or later.
If unsure, ask your IT team or search "dompurify CVE-2026-65902" on the vendor's site.
CVE-2026-65902 (dompurify) — CWE-501 / CVSS v3 6.1
Attack vector: remote (network-reachable) / unauthenticated
Attack surface: data.allowedTags / data.allowedAttributes / DEFAULT_ALLOWED_TAGS / DEFAULT_ALLOWED_ATTR
Patched: 3.4.7 — 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-501) exists in dompurify. Attackers reach the vulnerable code path via data.allowedTags without authentication.
Check the vendor advisory for the affected versions of dompurify. Attack surface: data.allowedTags / data.allowedAttributes / DEFAULT_ALLOWED_TAGS / DEFAULT_ALLOWED_ATTR.
Severity: Medium (CVSS 6.1/10). Risk of unauthorized operations or information disclosure.
Update to 3.4.7.
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 'dompurify' . 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 'dompurify' . | 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
dompurify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 dompurify to 3.4.7ステージング環境で 3.4.7 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-2026-65902 node-dompurify
- Ubuntu UBUNTU-CVE-2026-65902 node-dompurify
References
- advisory github.com
- advisory vulncheck.com
- advisory github.com
- advisory nvd.nist.gov
- patch github.com
- web github.com