CVE-2026-33438

MEDIUM

Stirling-PDF vulnerable to DoS via add-watermark

Title source: cna

Description

Stirling-PDF is a locally hosted web application that allows you to perform various operations on PDF files. Versions starting in 2.1.5 and prior to 2.5.2 have Denial of Service (DoS) vulnerability in the Stirling-PDF watermark functionality (`/api/v1/security/add-watermark` endpoint). The vulnerability allows authenticated users to cause resource exhaustion and server crashes by providing extreme values for the `fontSize` and `widthSpacer` parameters. Version 2.5.2 patches the issue.

References (1)

[X_Refsource_Confirm] https://github.com/Stirling-Tools/Stirling-PDF/security/advisories/GHSA-3932-2rfq-87xm

Scores

CVSS v3 6.5

EPSS 0.0004

EPSS Percentile 11.9%

Attack Vector NETWORK

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

Details

CWE

CWE-770

Status published

Products (2)

stirling/stirling_pdf 2.1.5 - 2.5.2

Stirling-Tools/Stirling-PDF >= 2.1.5, < 2.5.2

Published Mar 26, 2026

Tracked Since Mar 26, 2026