# CVE-2026-49286: PhpWeasyPrint vulnerable to PHAR deserialization via output filename (CVE-2023-28115 case-insensitive bypass)

> Attackers can achieve remote code execution by bypassing case-sensitive filename checks to trigger PHAR deserialization in PhpWeasyPrint.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Jun 2026
- **Updated:** 22 Jun 2026
- **Also known as:** GHSA-2fmj-p74r-3wjm

## What is CVE-2026-49286?

CVE-2026-49286 is a high-severity unsafe deserialization vulnerability in pontedilana php-weasyprint, published on 19 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2026-49286?

2 open source packages ship an affected version, including pontedilana/php-weasyprint.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `pontedilana/php-weasyprint` | Packagist | All versions | 2.6.0 |
| `pontedilana/php-weasyprint` | Packagist | All versions | 2.6.0 |

## How do I fix CVE-2026-49286?

Upgrade pontedilana/php-weasyprint to 2.6.0 or later.

## Is CVE-2026-49286 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-49286 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-49286 and fix it if it is affected.

What it is: CVE-2026-49286 is a high-severity unsafe deserialization vulnerability in pontedilana php-weasyprint, published on 19 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-49286 exists.

Affected packages and fixed versions:
- pontedilana/php-weasyprint (Packagist): affected all versions; fixed in 2.6.0
- pontedilana/php-weasyprint (Packagist): affected all versions; fixed in 2.6.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-49286/ (Markdown: https://insights.sbomify.com/CVE-2026-49286/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-49286
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-49286
- OSV: https://osv.dev/vulnerability/CVE-2026-49286

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-49286/
Summaries are generated and may contain mistakes; the official description above is the record.