Cyber Resilience

CVE-2026-49286

HighRCE

Published: 19 June 2026

Published
19 June 2026
Modified
22 June 2026
KEV Added
Patch
CVSS Score v3.1 8.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0056 42.2th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-49286 is a high-severity Deserialization of Untrusted Data (CWE-502) vulnerability. Its CVSS base score is 8.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 42.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability details

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://`,…

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`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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

Direct RCE via deserialization of untrusted PHAR data in a PHP library used for web content processing enables exploitation of public-facing applications.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

Affected Assets

PhpWeasyPrint
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-502

Penetration testing supplies malicious serialized objects, detecting unsafe deserialization and supporting corrective actions.

addresses: CWE-502

Evaluation of untrusted data handling (deserialization testing) reveals unsafe processing, which the required remediation process addresses.

addresses: CWE-502

Untrusted serialized data can be deserialized and observed inside the chamber, blocking gadget-chain exploitation outside the sandbox.

addresses: CWE-502

Validates or rejects untrusted serialized data before deserialization occurs.

addresses: CWE-502

Identifies and blocks malicious code introduced through deserialization of untrusted data at system boundaries.

addresses: CWE-502

Integrity verification of serialized information can detect tampering before deserialization occurs.

addresses: CWE-502

Provenance of associated data allows detection of untrusted sources before deserialization or processing occurs.

References