CVE-2023-34461
Cross-site Scripting (XSS) Availability in PyBB
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Cross-site Scripting (XSS) Availability in PyBB
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.
- Record
CVE-2023-34461- CVSS 3.1
- 4.6 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2023-38525
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.
- Record
EUVD-2023-38525- CVSS 3.1
- 4.6 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N - Updated
- 2026-11-03
NVD
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.
- Record
CVE-2023-34461- CVSS 3.1
- 4.6 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N - CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-34461 is a medium vulnerability (CVSS 4.6) in Benjjvi Pybb, published June 19, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.34%, the 27th percentile. No source names a fixed version.