CVE-2026-33418: DiceBear is an avatar library for designers and developers. Prior to version 9.4.2, the `ensureSize()` function in `@dicebear/converter` used a regex-...

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.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

0.38%

29.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-185

Affected Software

Vendor	Product	Versions
Dicebear	Dicebear	< 9.4.2

References

https://github.com/dicebear/dicebear/security/advisories/GHSA-7j2x-32w6-p43pMitigation, Vendor Advisory

Timeline

Published: Mar 24, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-33418?

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.

How severe is CVE-2026-33418?

CVE-2026-33418 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.38% probability of exploitation in the next 30 days.

How do I fix CVE-2026-33418?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.