CVE-2020-8294 - Vulnerability Details - OpenCVE

Description

A missing link validation in Nextcloud Server before 20.0.2, 19.0.5, 18.0.11 allows execution of a stored XSS attack using Internet Explorer when saving a 'javascript:' URL in markdown format.

Published: 2021-02-03

Score: 5.4 Medium

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

Nextcloud Server

affected

Version	Status	Constraints
`Fixed in 20.0.2, 19.0.5, 18.0.11`	affected	—

Configuration 1 [-]

OR	cpe:2.3:a:nextcloud:nextcloud_server::::::::
	cpe:2.3:a:nextcloud:nextcloud_server::::::::
	cpe:2.3:a:nextcloud:nextcloud_server::::::::

No data.

No data available yet.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
EUVD	EUVD-2020-29162	A missing link validation in Nextcloud Server before 20.0.2, 19.0.5, 18.0.11 allows execution of a stored XSS attack using Internet Explorer when saving a 'javascript:' URL in markdown format.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Changed

Confidentiality Impact Low

Integrity Impact Low

Availability Impact None

User Interaction Required

No CVSS v3.0

Access Vector Network

Access Complexity Medium

Authentication Single

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

The EPSS score is 0.00901.

Key SSVC decision points have not yet been added.

References

Link	Providers
https://hackerone.com/reports/1023787
https://nextcloud.com/security/advisory/?id=NC-SA-2021-002

History

No history.

Subscriptions

Nextcloud Nextcloud Server

MITRE

Status: PUBLISHED

Assigner: hackerone

Published: 2021-02-03T16:42:57.000Z

Updated: 2024-08-04T09:56:28.335Z

Reserved: 2020-01-28T00:00:00.000Z

Link: CVE-2020-8294

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-02-03T17:15:16.293

Modified: 2026-06-17T03:26:14.350

Link: CVE-2020-8294

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-79
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

{"containers": {"cna": {"affected": [{"product": "Nextcloud Server", "vendor": "n/a", "versions": [{"status": "affected", "version": "Fixed in 20.0.2, 19.0.5, 18.0.11"}]}], "descriptions": [{"lang": "en", "value": "A missing link validation in Nextcloud Server before 20.0.2, 19.0.5, 18.0.11 allows execution of a stored XSS attack using Internet Explorer when saving a 'javascript:' URL in markdown format."}], "problemTypes": [{"descriptions": [{"cweId": "CWE-79", "description": "Cross-site Scripting (XSS) - Stored (CWE-79)", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"dateUpdated": "2021-02-03T16:42:57.000Z", "orgId": "36234546-b8fa-4601-9d6f-f4e334aa8ea1", "shortName": "hackerone"}, "references": [{"tags": ["x_refsource_CONFIRM"], "url": "https://hackerone.com/reports/1023787"}, {"tags": ["x_refsource_CONFIRM"], "url": "https://nextcloud.com/security/advisory/?id=NC-SA-2021-002"}], "x_legacyV4Record": {"CVE_data_meta": {"ASSIGNER": "support@hackerone.com", "ID": "CVE-2020-8294", "STATE": "PUBLIC"}, "affects": {"vendor": {"vendor_data": [{"product": {"product_data": [{"product_name": "Nextcloud Server", "version": {"version_data": [{"version_value": "Fixed in 20.0.2, 19.0.5, 18.0.11"}]}}]}, "vendor_name": "n/a"}]}}, "data_format": "MITRE", "data_type": "CVE", "data_version": "4.0", "description": {"description_data": [{"lang": "eng", "value": "A missing link validation in Nextcloud Server before 20.0.2, 19.0.5, 18.0.11 allows execution of a stored XSS attack using Internet Explorer when saving a 'javascript:' URL in markdown format."}]}, "problemtype": {"problemtype_data": [{"description": [{"lang": "eng", "value": "Cross-site Scripting (XSS) - Stored (CWE-79)"}]}]}, "references": {"reference_data": [{"name": "https://hackerone.com/reports/1023787", "refsource": "CONFIRM", "url": "https://hackerone.com/reports/1023787"}, {"name": "https://nextcloud.com/security/advisory/?id=NC-SA-2021-002", "refsource": "CONFIRM", "url": "https://nextcloud.com/security/advisory/?id=NC-SA-2021-002"}]}}}, "adp": [{"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T09:56:28.335Z"}, "title": "CVE Program Container", "references": [{"tags": ["x_refsource_CONFIRM", "x_transferred"], "url": "https://hackerone.com/reports/1023787"}, {"tags": ["x_refsource_CONFIRM", "x_transferred"], "url": "https://nextcloud.com/security/advisory/?id=NC-SA-2021-002"}]}]}, "cveMetadata": {"assignerOrgId": "36234546-b8fa-4601-9d6f-f4e334aa8ea1", "assignerShortName": "hackerone", "cveId": "CVE-2020-8294", "datePublished": "2021-02-03T16:42:57.000Z", "dateReserved": "2020-01-28T00:00:00.000Z", "dateUpdated": "2024-08-04T09:56:28.335Z", "state": "PUBLISHED"}, "dataType": "CVE_RECORD", "dataVersion": "5.1"}

{"affected": [{"affectedData": [{"product": "Nextcloud Server", "vendor": "n/a", "versions": [{"status": "affected", "version": "Fixed in 20.0.2, 19.0.5, 18.0.11"}]}], "source": "support@hackerone.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*", "matchCriteriaId": "44D57333-C4F0-482B-92CB-91B8095733D0", "versionEndExcluding": "18.0.11", "vulnerable": true}, {"criteria": "cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*", "matchCriteriaId": "901AE378-7B1A-4D32-86FB-01971AAF0F48", "versionEndExcluding": "19.0.5", "versionStartIncluding": "19.0.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*", "matchCriteriaId": "715B9373-BCF9-4069-8C51-7714648C27E8", "versionEndExcluding": "20.0.2", "versionStartIncluding": "20.0.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "A missing link validation in Nextcloud Server before 20.0.2, 19.0.5, 18.0.11 allows execution of a stored XSS attack using Internet Explorer when saving a 'javascript:' URL in markdown format."}, {"lang": "es", "value": "Una falta comprobaci\u00f3n de enlace en Nextcloud Server versiones anteriores a 20.0.2, 19.0.5, 18.0.11, permite una ejecuci\u00f3n de un ataque de tipo XSS almacenado usando Internet Explorer cuando se guarda una URL \"javascript:\" en formato markdown"}], "id": "CVE-2020-8294", "lastModified": "2026-06-17T03:26:14.350", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "LOW", "cvssData": {"accessComplexity": "MEDIUM", "accessVector": "NETWORK", "authentication": "SINGLE", "availabilityImpact": "NONE", "baseScore": 3.5, "confidentialityImpact": "NONE", "integrityImpact": "PARTIAL", "vectorString": "AV:N/AC:M/Au:S/C:N/I:P/A:N", "version": "2.0"}, "exploitabilityScore": 6.8, "impactScore": 2.9, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "nvd@nist.gov", "type": "Primary", "userInteractionRequired": true}], "cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.4, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.3, "impactScore": 2.7, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2021-02-03T17:15:16.293", "references": [{"source": "support@hackerone.com", "tags": ["Permissions Required", "Third Party Advisory"], "url": "https://hackerone.com/reports/1023787"}, {"source": "support@hackerone.com", "tags": ["Vendor Advisory"], "url": "https://nextcloud.com/security/advisory/?id=NC-SA-2021-002"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Permissions Required", "Third Party Advisory"], "url": "https://hackerone.com/reports/1023787"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Vendor Advisory"], "url": "https://nextcloud.com/security/advisory/?id=NC-SA-2021-002"}], "sourceIdentifier": "support@hackerone.com", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}], "source": "support@hackerone.com", "type": "Secondary"}, {"description": [{"lang": "en", "value": "CWE-79"}], "source": "nvd@nist.gov", "type": "Primary"}]}