CVE-2026-27902

Svelte performance oriented web framework. Prior to version 5.53.5, errors from `transformError` were not correctly escaped prior to being embedded in the HTML output, causing potential HTML injection and XSS if attacker-controlled content is returned from `transformError`. Version 5.53.5 fixes the issue.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/sveltejs/svelte/commit/0298e979371bb583855c9810db79a70a551d22b9	Patch
https://github.com/sveltejs/svelte/releases/tag/svelte%405.53.5	Release Notes
https://github.com/sveltejs/svelte/security/advisories/GHSA-qgvg-pr8v-6rr3	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:svelte:svelte:*:*:*:*:*:node.js:*:*

History

No history.

Information

Published : 2026-02-26 02:16

Updated : 2026-03-05 14:48

NVD link : CVE-2026-27902

Mitre link : CVE-2026-27902

CVE.ORG link : CVE-2026-27902

JSON object : View

Products Affected

svelte

svelte

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

{"id": "CVE-2026-27902", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.4, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 2.5, "exploitabilityScore": 2.8}], "cvssMetricV40": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 5.3, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "PASSIVE", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "subIntegrityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "HIGH", "vulnConfidentialityImpact": "LOW", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "published": "2026-02-26T02:16:21.170", "references": [{"url": "https://github.com/sveltejs/svelte/commit/0298e979371bb583855c9810db79a70a551d22b9", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/sveltejs/svelte/releases/tag/svelte%405.53.5", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/sveltejs/svelte/security/advisories/GHSA-qgvg-pr8v-6rr3", "tags": ["Vendor Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-79"}]}], "descriptions": [{"lang": "en", "value": "Svelte performance oriented web framework. Prior to version 5.53.5, errors from `transformError` were not correctly escaped prior to being embedded in the HTML output, causing potential HTML injection and XSS if attacker-controlled content is returned from `transformError`. Version 5.53.5 fixes the issue."}, {"lang": "es", "value": "Framework web Svelte orientado al rendimiento. Antes de la versi\u00f3n 5.53.5, los errores de `transformError` no se escapaban correctamente antes de ser incrustados en la salida HTML, lo que causaba una posible inyecci\u00f3n HTML y XSS si el contenido controlado por el atacante se devuelve desde `transformError`. La versi\u00f3n 5.53.5 corrige el problema."}], "lastModified": "2026-03-05T14:48:34.240", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:svelte:svelte:*:*:*:*:*:node.js:*:*", "vulnerable": true, "matchCriteriaId": "EFAD88AD-F168-4A28-AAF0-17FBF87C580A", "versionEndExcluding": "5.53.5", "versionStartIncluding": "5.53.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}