CVE-2026-33418CWE-185

@dicebear/converter ensureSize() Vulnerable to SVG Dimension Capping Bypass via XML Comment Injection

High · published March 24, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
41.2
In the wild
Unconfirmed
What it is

DiceBear is an avatar library for designers and developers. Prior to version 9.4.2, the `ensureSize()` function in `@dicebear/converter` used a regex-based approach to rewrite SVG `width`/`height` attributes, capping them at 2048px to prevent denial of service. This size capping could be bypassed by crafting SVG input that causes the regex to match a non-functional occurrence of `<svg` before the actual SVG root element. When the SVG is subsequently rendered via `@resvg/resvg-js` on the Node.js code path, it renders at the attacker-specified dimensions, potentially causing out-of-memory crashes. In version 9.4.2, the regex-based approach has been replaced with XML-aware processing using `fast-xml-parser` to correctly identify and modify the SVG root element's attributes. Additionally, a `fitTo` constraint has been added to the `renderAsync` call as defense-in-depth, ensuring the rendered output is always bounded regardless of SVG content.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00490 · 41.2th percentile
Weakness
CWE-185 · Incorrect Regular Expression
Published
2026-03-24T13:25Z
EPSS history
Timeline
  • 24 MAR 13:25Z
    @dicebear/converter ensureSize() Vulnerable to SVG Dimension Capping Bypass via XML Comment Injection
    cvelistv5