# CVE-2023-23924: URI validation failure on SVG parsing in Dompdf

> Attackers can bypass URI validation in Dompdf SVG parsing to trigger arbitrary deserialization, potentially leading to remote code execution or file deletion.

- **Severity:** Critical 10.0 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/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:** 31 Jan 2023
- **Updated:** 10 Mar 2025
- **Also known as:** GHSA-3cw5-7cxw-v5qg

## What is CVE-2023-23924?

CVE-2023-23924 is a critical unsafe deserialization vulnerability in dompdf, published on 31 Jan 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Dompdf is an HTML to PDF converter. The URI validation on dompdf 2.0.1 can be bypassed on SVG parsing by passing `<image>` tags with uppercase letters. This may lead to arbitrary object unserialize on PHP < 8, through the `phar` URL wrapper. An attacker can exploit the vulnerability to call arbitrary URL with arbitrary protocols, if they can provide a SVG file to dompdf. In PHP versions before 8.0.0, it leads to arbitrary unserialize, that will lead to the very least to an arbitrary file deletion and even remote code execution, depending on classes that are available.

Weakness: CWE-863 (Incorrect Authorization), CWE-551 (Incorrect Behavior Order: Authorization Before Parsing and Canonicalization)

## Which versions are affected by CVE-2023-23924?

2 open source packages ship an affected version, including dompdf/dompdf. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `dompdf/dompdf` | Packagist | All versions | 2.0.2 |
| `dompdf/dompdf` | Packagist | All versions | 2.0.2 |

Products: Dompdf Project Dompdf.

## How do I fix CVE-2023-23924?

Upgrade dompdf/dompdf to 2.0.2 or later.

## Is CVE-2023-23924 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-23924 exists.

Public exploit code:

- CVE-2023-23924 (Dompdf - RCE) PoC (github_poc): https://github.com/motikan2010/CVE-2023-23924

## Other vulnerabilities in dompdf

- [CVE-2023-24813](https://insights.sbomify.com/CVE-2023-24813/): URI validation failure on SVG parsing. Bypass of CVE-2023-23924 (critical 10.0)
- [CVE-2021-3838](https://insights.sbomify.com/CVE-2021-3838/): PHAR Deserialization in dompdf/dompdf (critical 9.8)
- [CVE-2021-3902](https://insights.sbomify.com/CVE-2021-3902/): Improper Restriction of XML External Entity Reference in dompdf/dompdf (critical 9.8)
- [CVE-2022-28368](https://insights.sbomify.com/CVE-2022-28368/): Remote code injection in dompdf/dompdf (critical 9.8)
- [CVE-2014-5013](https://insights.sbomify.com/CVE-2014-5013/): DOMPDF Remote Code Execution (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-23924 and fix it if it is affected.

What it is: CVE-2023-23924 is a critical unsafe deserialization vulnerability in dompdf, published on 31 Jan 2023. 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-2023-23924 exists.

Affected packages and fixed versions:
- dompdf/dompdf (Packagist): affected all versions; fixed in 2.0.2
- dompdf/dompdf (Packagist): affected all versions; fixed in 2.0.2

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-2023-23924/ (Markdown: https://insights.sbomify.com/CVE-2023-23924/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-23924
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-23924
- OSV: https://osv.dev/vulnerability/CVE-2023-23924

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-23924/
Summaries are generated and may contain mistakes; the official description above is the record.