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Advisory details: vulnrichment / CVE-2026-59942
Advisory ID vulnrichment/CVE-2026-59942
Aliases
Summary 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 Published
Exploitability 0.5
Weighted Severity 0.0
Risk
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (1)
System Score Found at
cvssv4 6.3
ssvc Track
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
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 Found at None
Attack Vector (AV) Attack Complexity (AC) Attack Requirements (AT) Privileges Required (PR) User Interaction (UI) Vulnerable System Impact Confidentiality (VC) Vulnerable System Impact Integrity (VI) Vulnerable System Impact Availability (VA) Subsequent System Impact Confidentiality (SC) Subsequent System Impact Integrity (SI) Subsequent System Impact Availability (SA)

network

adjacent

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physical

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present

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low

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passive

active

high

low

none

high

low

none

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low

none

high

low

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high

low

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low

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Vector: SSVCv2/E:P/A:Y/T:P/P:M/B:A/M:M/D:T/2026-07-29T14:07:38Z/ Found at None

Vector: SSVCv2/E:P/A:Y/T:P/P:M/B:A/M:M/D:T/2026-07-29T14:07:38Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/59xxx/CVE-2026-59942.json

Source Advisory: vulnrichment/CVE-2026-59942

View SSVC decision tree
[{'Exploitation': 'poc'},
 {'Automatable': 'yes'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]