Description

WordPress Plugin MyBB Cross-Poster is prone to a cross-site scripting vulnerability because it fails to properly sanitize user-supplied input. An attacker may leverage this issue to execute arbitrary script code in the browser of an unsuspecting user in the context of the affected site. This can allow the attacker to steal cookie-based authentication credentials and launch other attacks. WordPress Plugin MyBB Cross-Poster version 1.0 is vulnerable.

Remediation

Edit the source code to ensure that input is properly sanitised or disable the plugin until a fix is available

References

https://github.com/BigTiger2020/word-press/blob/main/MyBB%20Cross-Poster.md

https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39338

https://wordpress.org/plugins/mybb-cross-poster/#description

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Severity

High

Classification

CVE-2021-39338 CWE-79 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

Tags

Missing Update XSS