Cyber Resilience

CVE-2023-34461

Medium

Published: 19 June 2023

Published
19 June 2023
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 4.6 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
EPSS Score 0.0012 30.4th percentile
Risk Priority 9 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-34461 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Pybb Project Pybb. Its CVSS base score is 4.6 (Medium).

Operationally, ranked at the 30.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

pybb project
pybb
0.1.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References