CVE-2023-34461Network attack vector

Stored cross-site scripting via unsafe post rendering

Published Jun 19, 2023 · Updated Dec 9, 2024

Stored cross-site scripting in benjjvi PyBB 0.1.0 allows remote authenticated users to execute JavaScript via crafted forum posts. The post.html Jinja template applies the safe filter to stored post content, bypassing automatic escaping while post creation accepts arbitrary HTML tags and unsafe link schemes. Exploitation requires posting privileges and another user to view the post, placing that viewer's browser data and page actions at risk.

CVSS severity5.4
Medium
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in benjjvi PyBB 0.1.0 allows remote authenticated users to execute JavaScript via crafted forum posts. The post.html Jinja template applies the safe filter to stored post content, bypassing automatic escaping while post creation accepts arbitrary HTML tags and unsafe link schemes. Exploitation requires posting privileges and another user to view the post, placing that viewer's browser data and page actions at risk.

The record

CVE
CVE-2023-34461
Published
Jun 19, 2023
Updated
Dec 9, 2024
Vendor
benjjvi
Product
PyBB
Classifications
CWE-79, T1189
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 19, 2023CVE publishedPublication date reported by the CVE source.
  2. Dec 9, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.1.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

benjjvi · PyBBversion=< 0.1.1

Published CVSS scores

4.6GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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