10

CVSS Score

3.1

-

CVSS Score

Basic Information

CVE ID

CVE-2023-24813

GHSA ID

GHSA-56gj-mvh6-rp75

EPSS Score

0.90172%

CWE

CWE-436

Published

2/7/2023

Updated

2/24/2023

KEV Status

Technology

PHP

Basic Information

CVE ID

GHSA ID

EPSS Score

CWE

Published

Updated

KEV Status

Technology

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CVE-2023-24813

CVE-2023-24813: URI validation failure on SVG parsing. Bypass of CVE-2023-23924

Summary

Due to the difference in the attribute parser of Dompdf and php-svg-lib, an attacker can still call arbitrary URLs with arbitrary protocols.

Details

Dompdf parses the href attribute of image tags with the following code:

src/Image/Cache.php line 135-150

function ($parser, $name, $attributes) use ($options, $parsed_url, $full_url) {
    if (strtolower($name) === "image") {
        $attributes = array_change_key_case($attributes, CASE_LOWER);
        $url = $attributes["xlink:href"] ?? $attributes["href"];
        if (!empty($url)) {
            $inner_full_url = Helpers::build_url($parsed_url["protocol"], $parsed_url["host"], $parsed_url["path"], $url);
            if ($inner_full_url === $full_url) {
                throw new ImageException("SVG self-reference is not allowed", E_WARNING);
            }
            [$resolved_url, $type, $message] = self::resolve_url($url, $parsed_url["protocol"], $parsed_url["host"], $parsed_url["path"], $options);
            if (!empty($message)) {
                throw new ImageException("This SVG document references a restricted resource. $message", E_WARNING);
            }
        }
    }
},

As you can see from the code snippet above, it respects xlink:href even if href is specified.

$url = $attributes["xlink:href"] ?? $attributes["href"];

However, php-svg-lib, which is later used to parse the svg file, parses the href attribute with the following code:

src/Svg/Tag/Image.php line 51-57

if (isset($attributes['xlink:href'])) {
    $this->href = $attributes['xlink:href'];
}

if (isset($attributes['href'])) {
    $this->href = $attributes['href'];
}

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 attribute.

Miggo Vulnerability Database

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CVE-2023-24813

CVE-2023-24813:

10

CVSS Score

3.1

-

CVSS Score

Basic Information

CVE ID

CVE-2023-24813

GHSA ID

GHSA-56gj-mvh6-rp75

EPSS Score

0.90172%

CWE

CWE-436

Published

2/7/2023

Updated

2/24/2023

KEV Status

Technology

PHP

Basic Information

CVE ID

GHSA ID

EPSS Score

CWE

Published

Updated

KEV Status

Technology

Technical Details

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Package Name	Ecosystem	Vulnerable Versions	First Patched Version
dompdf/dompdf	composer	= 2.0.2	2.0.3

Technical Details

Vulnerability Intelligence
Miggo AI

Root Cause Analysis

The vulnerability stems from the discrepancy between how Dompdf's Cache.php and php-svg-lib's Image.php handle SVG attributes. Dompdf's code (pre-patch) only validated the first non-empty attribute between 'xlink:href' and 'href', while php-svg-lib's code would ultimately use 'href' if both were present. The anonymous function in Cache.php failed to validate both attributes independently, allowing attackers to bypass security checks by exploiting this parsing inconsistency.

Vulnerable functions

Only Mi**o us*rs **n s** t*is s**tion

WAF Protection Rules

WAF Rule

W** rul*s *v*il**l* *or Mi**o *ustom*rs only.W** rul*s *v*il**l* *or Mi**o *ustom*rs only.W** rul*s *v*il**l* *or Mi**o *ustom*rs only.W** rul*s *v*il**l* *or Mi**o *ustom*rs only.W** rul*s *v*il**l* *or Mi**o *ustom*rs only.W** rul*s *v*il**l* *or Mi**o *ustom*rs only.W** rul*s *v*il**l* *or Mi**o *ustom*rs only.W** rul*s *v*il**l* *or Mi**o *ustom*rs only.W** rul*s *v*il**l* *or Mi**o *ustom*rs only.W** rul*s *v*il**l* *or Mi**o *ustom*rs only.

Reasoning

*v*il**l* *or Mi**o *ustom*rs only.*v*il**l* *or Mi**o *ustom*rs only.*v*il**l* *or Mi**o *ustom*rs only.*v*il**l* *or Mi**o *ustom*rs only.*v*il**l* *or Mi**o *ustom*rs only.*v*il**l* *or Mi**o *ustom*rs only.*v*il**l* *or Mi**o *ustom*rs only.*v*il**l* *or Mi**o *ustom*rs only.*v*il**l* *or Mi**o *ustom*rs only.*v*il**l* *or Mi**o *ustom*rs only.

10

-

Basic Information

Basic Information

Concerned about an active attack path?

CVE-2023-24813: URI validation failure on SVG parsing. Bypass of CVE-2023-23924

Summary

Details

CVE-2023-24813:

10

-

Basic Information

Basic Information

Technical Details

Technical Details

Vulnerability Intelligence
Miggo AI

Root Cause Analysis

Vulnerable functions

WAF Protection Rules

WAF Rule

Reasoning

Vulnerability Intelligence
Miggo AI

Detect and Respond To Threats Faster.

Basic Information

Basic Information

Vulnerability Intelligence
Miggo AI

Root Cause Analysis

Vulnerable functions

WAF Protection Rules

WAF Rule

Reasoning

Technical Details

10

10

CVE-2023-24813: URI validation failure on SVG parsing. Bypass of CVE-2023-23924

Summary

Details

Impact

10

-

Basic Information

Basic Information

Concerned about an active attack path?

CVE-2023-24813: URI validation failure on SVG parsing. Bypass of CVE-2023-23924

Summary

Details

CVE-2023-24813:

10

-

Basic Information

Basic Information

Technical Details

Technical Details

Vulnerability IntelligenceMiggo AI

Root Cause Analysis

Vulnerable functions

WAF Protection Rules

WAF Rule

Reasoning

Vulnerability IntelligenceMiggo AI

Basic Information

Basic Information

Vulnerability IntelligenceMiggo AI

Root Cause Analysis

Vulnerable functions

WAF Protection Rules

WAF Rule

Reasoning

Technical Details

10

10

CVE-2023-24813: URI validation failure on SVG parsing. Bypass of CVE-2023-23924

Summary

Details

Impact

Vulnerability Intelligence
Miggo AI

Vulnerability Intelligence
Miggo AI

Vulnerability Intelligence
Miggo AI