Vulnerability in dompdf/dompdf (CVE-2026-56722)
Summary
Vulnerability in dompdf/dompdf (CVE-2026-56722). Risk of unauthorized operations or information disclosure. Exploitable via chroot. Mitigation: upgrade to 3.1.6 or later.
Original description
The description as published by the source.
Dompdf is an HTML to PDF converter for PHP. In versions 3.15 and prior, aAn attacker who controls the HTML input can bypass this restriction by embedding a target file path inside an SVG image delivered through a data: URI, because dompdf processes the SVG twice and the second pass does not enforce the same protections as the first. When rendering, dompdf hands the SVG to the separate php-svg-lib library with external references forced on, and that library has no knowledge of the chroot directory, blocks only the phar:// scheme, and ultimately reads the referenced file with no path or protocol validation. This lets an external, unauthenticated attacker read arbitrary image files from the server's file system in the default configuration. This issue has been fixed in version 3.16.
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-2026-56722 has been found in dompdf/dompdf.
Attackers can target a specific entry point like chroot over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 5.3/10.
What to do: upgrade dompdf/dompdf to 3.1.6 or later.
If unsure, ask your IT team or search "dompdf/dompdf CVE-2026-56722" on the vendor's site.
CVE-2026-56722 (dompdf/dompdf) — CWE-20 / CVSS v3 5.3
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: chroot
Patched: 3.1.6 — 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-20) exists in dompdf/dompdf. Attackers reach the vulnerable code path via chroot without authentication.
Check the vendor advisory for the affected versions of dompdf/dompdf. Attack surface: chroot.
Severity: Medium (CVSS 5.3/10). Risk of unauthorized operations or information disclosure.
Update to 3.1.6.
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 'dompdf/dompdf' . 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 'dompdf/dompdf' . | 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
dompdf/dompdf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 dompdf/dompdf to 3.1.6ステージング環境で 3.1.6 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-2026-56722 php-dompdf
- Ubuntu UBUNTU-CVE-2026-56722 php-dompdf
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov
- package github.com
- patch github.com
- patch github.com
- web github.com
- web github.com