CVE-2026-33438CWE-770

Stirling-PDF vulnerable to DoS via add-watermark

Medium · published March 26, 2026

CVSS v3.1
6.5
EPSS
0%
Percentile
37.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00444 · 37.6th percentile
Weakness
CWE-770 · Allocation of Resources Without Limits or Throttling
Published
2026-03-26T16:58Z
EPSS history
Timeline
  • 26 MAR 16:58Z
    Stirling-PDF vulnerable to DoS via add-watermark
    cvelistv5