Vulnerability in enshrined/svg-sanitize (CVE-2026-107379)
Summary
Vulnerability in enshrined/svg-sanitize (CVE-2026-107379). Risk of unauthorized operations or information disclosure. Exploitable via POST /wp/v2/media. Mitigation: upgrade to 1.0.0 or later.
Original description
The description as published by the source.
Summary
A crafted SVG file (1009 bytes) crashes the PHP process when sanitized by enshrined/svg-sanitize (any version through 0.22.x). The sanitizer's cleanAttributesOnWhitelist() method calls DOMElement::removeAttribute() twice on the same attribute name — first removing the explicit attribute, then attempting to remove the DTD #FIXED default — triggering a PHP ext/dom type confusion that kills the PHP-FPM worker.
Affected installations:
- enshrined/svg-sanitize: 45.2M Packagist downloads, 1.3M/month, 90+ dependents
- WordPress Safe SVG plugin: 1M+ active installs
- TYPO3: svg-sanitize integrated into core since v9
- Drupal: community module wrapping svg-sanitize
Vulnerability Details
Trigger Flow
Sanitizer::sanitize($malicious_svg)
→ DOMDocument::loadXML() — parses DTD, creates XML_ATTRIBUTE_DECL for #FIXED attr
→ startClean() → cleanAttributesOnWhitelist($svgElement)
→ "badhref" NOT in allowedAttrs
→ removeAttribute("badhref") ← removes explicit attribute (safe)
→ stripos("badhref", "href") = TRUE
→ getAttribute("badhref") ← returns DTD #FIXED default value
→ isHrefSafeValue("javascript:x") ← returns FALSE
→ removeAttribute("badhref") ← hits XML_ATTRIBUTE_DECL → CRASH
Root cause in svg-sanitize: The sanitizer does not strip DOCTYPE/DTD declarations before processing. The cleanAttributesOnWhitelist() method at Sanitizer.php:303-330 has a double-removal pa…
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-2026-107379 has been found in enshrined/svg-sanitize.
Attackers can target a specific entry point like POST /wp/v2/media over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 6.5/10.
What to do: upgrade enshrined/svg-sanitize to 1.0.0 or later.
If unsure, ask your IT team or search "enshrined/svg-sanitize CVE-2026-107379" on the vendor's site.
CVE-2026-107379 (enshrined/svg-sanitize) — CWE-770 / CVSS v3 6.5
Attack vector: remote (network-reachable) / no user interaction
Attack surface: POST /wp/v2/media / HrEf / href / evil.svg
Patched: 1.0.0 — 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.
A vulnerability (CWE-770) exists in enshrined/svg-sanitize. Attackers reach the vulnerable code path via POST /wp/v2/media.
Check the vendor advisory for the affected versions of enshrined/svg-sanitize. Attack surface: POST /wp/v2/media / HrEf / href / evil.svg.
Severity: Medium (CVSS 6.5/10). Risk of unauthorized operations or information disclosure.
Update to 1.0.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual POST /wp/v2/media requests with malformed payloads or SQL meta-characters. Run grep -r 'enshrined/svg-sanitize' . 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 'enshrined/svg-sanitize' . | 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
enshrined/svg-sanitize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 'POST /wp/v2/media' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /wp/v2/media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 enshrined/svg-sanitize to 1.0.0ステージング環境で 1.0.0 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。
-
4Post-deployment verification verify
Replay attack against POST /wp/v2/media 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。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com
- web github.com
- web github.com