9.8
CRITICAL
CVE-2021-3838
DomPDF PHAR Deserialization Remote Code Execution
Description

DomPDF before version 2.0.0 is vulnerable to PHAR deserialization due to a lack of checking on the protocol before passing it into the file_get_contents() function. An attacker who can upload files of any type to the server can pass in the phar:// protocol to unserialize the uploaded file and instantiate arbitrary PHP objects. This can lead to remote code execution, especially when DOMPdf is used with frameworks with documented POP chains like Laravel or vulnerable developer code.

INFO

Published Date :

Nov. 15, 2024, 11:15 a.m.

Last Modified :

Nov. 19, 2024, 5:11 p.m.

Remotely Exploitable :

Yes !

Impact Score :

5.9

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2021-3838 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Dompdf_project dompdf
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-3838.

URL Resource
https://github.com/dompdf/dompdf/commit/99aeec1efec9213e87098d42eb09439e7ee0bb6a Patch
https://huntr.com/bounties/0bdddc12-ff67-4815-ab9f-6011a974f48e Exploit Issue Tracking Patch Third Party Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-3838 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-3838 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    Nov. 19, 2024

    Action Type Old Value New Value
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://github.com/dompdf/dompdf/commit/99aeec1efec9213e87098d42eb09439e7ee0bb6a No Types Assigned https://github.com/dompdf/dompdf/commit/99aeec1efec9213e87098d42eb09439e7ee0bb6a Patch
    Changed Reference Type https://huntr.com/bounties/0bdddc12-ff67-4815-ab9f-6011a974f48e No Types Assigned https://huntr.com/bounties/0bdddc12-ff67-4815-ab9f-6011a974f48e Exploit, Issue Tracking, Patch, Third Party Advisory
    Added CPE Configuration OR *cpe:2.3:a:dompdf_project:dompdf:*:*:*:*:*:*:*:* versions up to (excluding) 2.0.0
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Nov. 18, 2024

    Action Type Old Value New Value
    Added CVSS V3.1 CISA-ADP AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
  • CVE Received by [email protected]

    Nov. 15, 2024

    Action Type Old Value New Value
    Added Description DomPDF before version 2.0.0 is vulnerable to PHAR deserialization due to a lack of checking on the protocol before passing it into the file_get_contents() function. An attacker who can upload files of any type to the server can pass in the phar:// protocol to unserialize the uploaded file and instantiate arbitrary PHP objects. This can lead to remote code execution, especially when DOMPdf is used with frameworks with documented POP chains like Laravel or vulnerable developer code.
    Added Reference huntr.dev https://huntr.com/bounties/0bdddc12-ff67-4815-ab9f-6011a974f48e [No types assigned]
    Added Reference huntr.dev https://github.com/dompdf/dompdf/commit/99aeec1efec9213e87098d42eb09439e7ee0bb6a [No types assigned]
    Added CWE huntr.dev CWE-502
    Added CVSS V3 huntr.dev AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-3838 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-3838 weaknesses.

CVSS31 - Vulnerability Scoring System
Attack Vector
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Scope
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