Stored XSS via unencoded smiley pack URLs
Published Nov 2, 2023 · Updated Feb 27, 2025
Stored XSS in phpBB 3.3.10 and earlier allows remote authenticated users with administrator access to inject JavaScript through smiley packs. The Smiley Pack Handler reads each image URL from a .pak file and stores it without URL encoding, allowing JavaScript-bearing values to reach rendered pages. Exploitation requires ACP administrative access and importing a crafted pack; the injected script runs when affected smiley markup is rendered.
Summary
What happened
Stored XSS in phpBB 3.3.10 and earlier allows remote authenticated users with administrator access to inject JavaScript through smiley packs. The Smiley Pack Handler reads each image URL from a .pak file and stores it without URL encoding, allowing JavaScript-bearing values to reach rendered pages. Exploitation requires ACP administrative access and importing a crafted pack; the injected script runs when affected smiley markup is rendered.
The record
- CVE
- CVE-2023-5917
- Published
- Nov 2, 2023
- Updated
- Feb 27, 2025
- Vendor
- phpBB
- Product
- phpBB
- Classifications
- CWE-79, T1059.007
- Attack vector
- network
- Privileges
- admin
Timeline
How it unfolded
- Nov 2, 2023CVE publishedPublication date reported by the CVE source.
- Feb 27, 2025Record 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.
- Affected versionversion=3.3.0
- Affected versionversion=3.3.1
- Affected versionversion=3.3.10
- Affected versionversion=3.3.2
- Affected versionversion=3.3.3
- Affected versionversion=3.3.4
- Affected versionversion=3.3.5
- Affected versionversion=3.3.6
- Affected versionversion=3.3.7
- Affected versionversion=3.3.8
- Affected versionversion=3.3.9
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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