XSS in Benjjvi Pybb

CVE-2023-34461

PyBB is an open source bulletin board. A manual code review of the PyBB bulletin board server has revealed that a vulnerability could have been exploited in which users could submit any type of HTML tag, and have said tag run. For example, a malicious `<a>` that looks like ```<a href=javascript:alert (1)>xss</a>``` could have been used to run code through JavaScript on the client side. The problem has been patched as of commit `5defd92`, and users are advised to upgrade. Attackers do need posting privilege in order to exploit this vulnerability. This vulnerability is present within the 0.1.0 release, and users are advised to upgrade to 0.1.1. Users unable to upgrade may be able to work around the attack by either; Removing the ability to create posts, removing the `|safe` tag from the Jinja2 template titled "post.html" in templates or by adding manual validation of links in the post creation section.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.003 (26.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.6 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2023-34461?
CVE-2023-34461 is a medium-severity vulnerability in Benjjvi Pybb, classified under Cross-site Scripting. CVSS score: 4.6/10. Published 2023-06-19.
How severe is CVE-2023-34461?
Medium severity. CVSS v3 base score is 4.6 out of 10.