Cross-site scripting via trusted-port URL validation
Published Mar 18, 2021 · Updated Aug 3, 2024
Cross-site scripting in Increments Qiita::Markdown before 0.33.0 allows remote attackers to execute script via a crafted iframe URL. The iframe transformer trusted URLs based on port 80 or 443 without requiring an HTTP or HTTPS scheme, preserving an attacker-controlled javascript URL in rendered HTML. Exploitation requires a user to view content rendered from attacker-controlled Markdown, allowing script execution in that browser context.
Summary
What happened
Cross-site scripting in Increments Qiita::Markdown before 0.33.0 allows remote attackers to execute script via a crafted iframe URL. The iframe transformer trusted URLs based on port 80 or 443 without requiring an HTTP or HTTPS scheme, preserving an attacker-controlled javascript URL in rendered HTML. Exploitation requires a user to view content rendered from attacker-controlled Markdown, allowing script execution in that browser context.
The record
- CVE
- CVE-2021-28796
- Published
- Mar 18, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-79
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 18, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
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Published CVSS scores
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Attacks
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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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