Dompdf PHAR redirect

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.6$0-$5k0.00

Summaryinfo

A vulnerability has been found in Dompdf and classified as critical. This affects an unknown function of the component PHAR Handler. Performing a manipulation results in redirect. This vulnerability was named CVE-2021-3838. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as critical, was found in Dompdf (the affected version unknown). This affects an unknown part of the component PHAR Handler. The manipulation with an unknown input leads to a redirect vulnerability. CWE is classifying the issue as CWE-601. A web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a Redirect. This simplifies phishing attacks. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was presented 07/18/2023. It is possible to read the advisory at rapid7.com. This vulnerability is uniquely identified as CVE-2021-3838 since 09/29/2021. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1204.001 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 280147 (Debian dla-4427 : php-dompdf - security update), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (280147). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.6

VulDB Base Score: 5.5
VulDB Temp Score: 5.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Redirect
CWE: CWE-601
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 280147
Nessus Name: Debian dla-4427 : php-dompdf - security update

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

09/29/2021 🔍
07/18/2023 +657 days 🔍
07/18/2023 +0 days 🔍
12/30/2025 +896 days 🔍

Sourcesinfo

Advisory: rapid7.com
Status: Not defined

CVE: CVE-2021-3838 (🔍)
GCVE (CVE): GCVE-0-2021-3838
GCVE (VulDB): GCVE-100-234363

Entryinfo

Created: 07/18/2023 13:19
Updated: 12/30/2025 18:52
Changes: 07/18/2023 13:19 (34), 11/18/2024 17:20 (27), 12/30/2025 18:52 (2)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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