CVE-2021-27889

View on CVE.org

Published Mar 15, 2021 CVSS 3.1 · 6.1 Medium EPSS 5.1% KEV · Not listed

Description

Cross-site Scripting (XSS) vulnerability in MyBB before 1.8.26 via Nested Auto URL when parsing messages.

Analysis

No analysis available yet

Affected Products

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

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

cpe:2.3:a:mybb:mybb:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No remediation available yet

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
EUVD	EUVD-2021-14626	Cross-site Scripting (XSS) vulnerability in MyBB before 1.8.26 via Nested Auto URL when parsing messages.

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

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 None

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

Exploit prediction score: 5.1% (5.072% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
http://packetstormsecurity.com/files/161908/MyBB-1.8.25-Remote-Command-Execution.html
https://blog.sonarsource.com/mybb-remote-code-execution-chain
https://github.com/mybb/mybb/security/advisories/GHSA-xhj7-3349-mqcm

History

No history.

Subscriptions

Mybb Mybb

Weaknesses

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

Sources

CVE record Updated: Aug 3, 2024, 9:33 PM

Status: PUBLISHED
Assigner: mitre
Published: Mar 15, 2021, 4:57 PM
Updated: Aug 3, 2024, 9:33 PM
Reserved: Mar 2, 2021, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 3:45 AM

Status: Modified
Published: Mar 15, 2021, 5:15 PM
Modified: Jun 17, 2026, 3:45 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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