CVE-2026-59942

Publication date 28 July 2026

Last updated 7 August 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

7.5 · High

Score breakdown

Description

Dompdf is an HTML to PDF converter for PHP. Versions 3.15 and prior are vulnerable to a Denial of Service (DoS) attack via resource exhaustion. An attacker can crash the PHP process by providing a specially crafted HTML document containing a single image with massive dimensions (e.g., 30,000x30,000 pixels). While Dompdf implements internal checks to validate image dimensions, these can be bypassed by using a high-entropy image (such as random noise) encoded in Base64 and wrapped in specific CSS containers. The vulnerability exists because the dimension validation happens early, but the resource allocation for calculating the object's bounding box and internal buffers during the rendering phase does not strictly limit the cumulative CPU time or memory usage for a single object that has passed the initial check. An unauthenticated remote attacker can cause a complete Denial of Service on the web server by submitting a crafted HTML string. This affects any application that allows users to provide HTML content or URLs that are subsequently converted to PDF using Dompdf. This issue has been fixed in version 3.16.

Status

Package Ubuntu Release Status
php-dompdf 26.04 LTS resolute Not in release
24.04 LTS noble Not in release
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation

Severity score breakdown

CVSS version:

Base score 6.3 · Medium

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Base score 7.5 · High

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

References

Other references

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