How severe is CVE-2023-34461?

CVE-2023-34461 has a CVSS 3.x base score of 4.6, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2023-34461 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-34461?

CVE-2023-34461 affects Pybb Project Pybb. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-34461?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-34461 published?

CVE-2023-34461 was published on 2023-06-19 and last updated on 2026-06-17.

CVE-2023-34461

CVE-2023-34461 is a medium-severity vulnerability in Pybb Project Pybb with a CVSS 3.x base score of 4.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 4.6)
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Pybb Project Pybb
Published: 2023-06-19
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2023-34461?: CVE-2023-34461 has a CVSS 3.x base score of 4.6, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2023-34461 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-34461?: CVE-2023-34461 affects Pybb Project Pybb. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-34461?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-34461 published?: CVE-2023-34461 was published on 2023-06-19 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:pybb_project:pybb:0.1.0:*:*:*:*:*:*:*

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