CVE-2023-24813 URI validation failure on SVG parsing. Bypass of CVE-2023-23924
Attacker can bypass URI validation in Dompdf to trigger SSRF and potential remote code execution via malicious SVG files.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-24813?
CVE-2023-24813 is a critical server-side request forgery vulnerability in dompdf, published on 7 Feb 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 written in php. Due to the difference in the attribute parser of Dompdf and php-svg-lib, an attacker can still call arbitrary URLs with arbitrary protocols. Dompdf parses the href attribute of `image` tags and respects `xlink:href` even if `href` is specified. However, php-svg-lib, which is later used to parse the svg file, parses the href attribute. Since `href` is respected if both `xlink:href` and `href` is specified, it's possible to bypass the protection on the Dompdf side by providing an empty `xlink:href` attribute. An attacker can exploit the vulnerability to call arbitrary URLs with arbitrary protocols if they provide an SVG file to the Dompdf. In PHP versions before 8.0.0, it leads to arbitrary unserialize, which will lead, at the very least, to arbitrary file deletion and might lead to remote code execution, depending on available classes. This vulnerability has been addressed in commit `95009ea98` which has been included in release version 2.0.3. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Weakness: CWE-436
Which versions are affected by CVE-2023-24813?
2 open source packages ship an affected version, including dompdf/dompdf. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
dompdf/dompdf Packagist | From 2.0.2 | 2.0.3 |
dompdf/dompdf Packagist | From 2.0.2 | 2.0.3 |
Products include Dompdf Project Dompdf.
How do I fix CVE-2023-24813?
Upgrade dompdf/dompdf to 2.0.3 or later.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2023-24813 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-24813 exists.
Other vulnerabilities in dompdf
Sources
Also known as DEBIAN-CVE-2023-24813, GHSA-56gj-mvh6-rp75.