Cross-Site Scripting in lazysizes
Versions of lazysizes prior to 5.2.1-rc1 are vulnerable to Cross-Site Scripting. The video-embed plugin fails to sanitize the following attributes: data-vimeo, data-vimeoparams, data-youtube and data-ytparams. This allows attackers to execute arbitrary JavaScript in a victim's browser if the attacker has control over the vulnerable attributes.
Recommendation
Upgrade to version 5.2.1-rc1 or later.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| npm package | lazysizes | < 5.2.1-rc1 | 5.2.1-rc1 |
References
- Weakness (CWE)
CWE-79- Platform
- npm
- Package
lazysizes- Disclosed
- 03.09.2020
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-w4vp-3mq7-7v82 - CC BY 4.0
Vulnerability history: lazysizes
All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 2
- First → latest
- 09.2020 12.2021
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- High 1
- Medium 1
Disclosures per year
- 2020: 1
- 2021: 1
- 2022: 0
- 2023: 0
- 2024: 0
- 2025: 0
- 2026: 0
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Cross-Site Scripting in lazysizes this entry
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