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

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.

Published: 2026-03-24 Last update: 2026-03-24 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-33418 is rated Low Risk (32.1/100): CVSS High severity, with low exploitation likelihood (EPSS 0.02%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-33418

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-22 0.06% 0.02% -0.04%
2 2026-03-30 0.04% 0.06% +0.01%
3 2026-03-25 0.04%

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-33418

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-33418

GitHub Security Advisory for CVE-2026-33418

GHSA-7j2x-32w6-p43p · Severity: high · Ecosystem: npm — SVG Dimension Capping Bypass via XML Comment Injection in @dicebear/converter ensureSize()

Affected software / configurations for CVE-2026-33418

Vendor Product Version Raw CPE
dicebear dicebear < 9.4.2 cpe:2.3:a:dicebear:dicebear:*:*:*:*:*:*:*:*

References for CVE-2026-33418

cvelogic Threat Intelligence