How severe is CVE-2021-3838?

CVE-2021-3838 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-3838 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3838?

CVE-2021-3838 affects Dompdf Project Dompdf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-3838?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2021-3838 have an EU (EUVD) identifier?

Yes. CVE-2021-3838 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-3197.

When was CVE-2021-3838 published?

CVE-2021-3838 was published on 2024-11-15 and last updated on 2026-06-17.

CVE-2021-3838

CVE-2021-3838 is a critical-severity vulnerability in Dompdf Project Dompdf with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-502.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-3197
Weakness: CWE-502
Affected product: Dompdf Project Dompdf
Published: 2024-11-15
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-3838?: 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.
How severe is CVE-2021-3838?: CVE-2021-3838 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-3838 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3838?: CVE-2021-3838 affects Dompdf Project Dompdf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-3838?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2021-3838 have an EU (EUVD) identifier?: Yes. CVE-2021-3838 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-3197.
When was CVE-2021-3838 published?: CVE-2021-3838 was published on 2024-11-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:dompdf_project:dompdf:*:*:*:*:*:*:*:*

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