CVE-2021-27889 - Vulnerability Details - OpenCVE

Description

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

Published: 2021-03-15

Score: 6.1 Medium

EPSS: 5.1% 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

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 vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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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.

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.

The EPSS score is 0.05072.

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

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2021-03-15T16:57:02.000Z

Updated: 2024-08-03T21:33:17.199Z

Reserved: 2021-03-02T00:00:00.000Z

Link: CVE-2021-27889

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-03-15T17:15:22.517

Modified: 2026-06-17T03:45:33.900

Link: CVE-2021-27889

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

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

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