Unsafe Deserialization in pontedilana/php-weasyprint (CVE-2026-49286)
Summary
Vulnerability in pontedilana/php-weasyprint (CVE-2026-49286). Successful exploitation can lead to full system takeover. Exploitable via eb8accc. Mitigation: upgrade to 2.6.0 or later.
Original description
The description as published by the source.
PhpWeasyPrint is a PHP library allowing PDF generation from a URL or an HTML page. Prior to version 2.6.0, pontedilana/php-weasyprint guarded the output filename against the phar:// stream wrapper with a case-sensitive blacklist. PHP stream wrappers are case-insensitive, so PHAR://, Phar://, etc. bypass the check and reach fileExists() (file_exists()) in prepareOutput(). On PHP 7 (which the library still supports — PHP 7.4+), this triggers deserialization of a crafted PHAR archive's metadata, leading to remote code execution. This is the patch-bypass of CVE-2023-28115. The same issue and fix were handled upstream in KnpLabs/snappy (GHSA-92rv-4j2h-8mjj). PhpWeasyPrint version 2.6.0 contains a patch for the issue.
Source: NIST National Vulnerability Database 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-2026-49286 has been found in pontedilana/php-weasyprint.
Attackers can target a specific entry point like eb8accc over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 8.1/10.
What to do: upgrade pontedilana/php-weasyprint to 2.6.0 or later.
If unsure, ask your IT team or search "pontedilana/php-weasyprint CVE-2026-49286" on the vendor's site.
CVE-2026-49286 (pontedilana/php-weasyprint) — CWE-502 / CVSS v3 8.1
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: eb8accc / file / phar / PHAR
Patched: 2.6.0 — 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.
Unsafe deserialization (CWE-502) exists in pontedilana/php-weasyprint. Attackers reach the vulnerable code path via eb8accc without authentication.
Check the vendor advisory for the affected versions of pontedilana/php-weasyprint. Attack surface: eb8accc / file / phar / PHAR.
Severity: High (CVSS 8.1/10). Successful exploitation can lead to full system takeover.
Update to 2.6.0.
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 'pontedilana/php-weasyprint' . 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 'pontedilana/php-weasyprint' . | 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
pontedilana/php-weasyprint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 pontedilana/php-weasyprint to 2.6.0ステージング環境で 2.6.0 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 github.com
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- patch github.com
- web github.com
- web github.com