CVE-2026-33418 @dicebear/converter ensureSize() Vulnerable to SVG Dimension Capping Bypass via XML Comment Injection

Q: Which versions are affected by CVE-2026-33418?

2 open source packages ship an affected version, including @dicebear/converter. It affects 1 product.

Q: Is CVE-2026-33418 being exploited?

There is no known exploitation of CVE-2026-33418 in the wild and no public exploit code.

Q: How do I fix CVE-2026-33418?

Upgrade @dicebear/converter to 9.4.2 or later.

High 7.5 Published 24 Mar 2026 Updated 24 Mar 2026

Attackers can bypass SVG dimension limits to cause out-of-memory crashes in applications using the DiceBear avatar library.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-33418?

CVE-2026-33418 is a high-severity denial of service vulnerability in dicebear, published on 24 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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.

Weakness: CWE-185

Which versions are affected by CVE-2026-33418?

2 open source packages ship an affected version, including @dicebear/converter. It affects 1 product.

Package	Affected	Fixed in
`@dicebear/converter` npm	All versions	`9.4.2`
`@dicebear/converter` npm	All versions	`9.4.2`

Products include Dicebear Dicebear.

How do I fix CVE-2026-33418?

Upgrade @dicebear/converter to 9.4.2 or later.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-33418 being exploited?

There is no known exploitation of CVE-2026-33418 in the wild and no public exploit code.

Sources

Also known as GHSA-7j2x-32w6-p43p.