PatchTheCVECVE-2020-7642: lazysizes through 5.2.0 allows execution of malicious JavaScript
CVE-2020-7642 is a medium-severity flaw (CVSS 5.4) affecting lazysizes. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
lazysizes through 5.2.0 allows execution of malicious JavaScript. The following attributes are not sanitized by the video-embed plugin: data-vimeo, data-vimeoparams, data-youtube and data-ytparams which can be abused to inject malicious JavaScript.
Why this priority
- Public exploit reference
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.4 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | Low |
| User interaction | Required |
| EPSS exploit chance | 0.9% (top 41%) |
| CISA exploited list | No |
| Weakness | CWE-79 |
| Published | 2020-04-22 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2020-7642?
lazysizes: upgrade to newer than 5.2.0. Exact commands for each OS are on this page.
Is CVE-2020-7642 being exploited?
CVE-2020-7642 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2020-7642 affect?
CVE-2020-7642 affects lazysizes. Severity is medium (CVSS 5.4). lazysizes through 5.2.0 allows execution of malicious JavaScript. The following attributes are not sanitized by the video-embed plugin: data-vimeo, data-vimeoparams, data-youtube and data-ytparams which can be abused to inject malicious Jav
How urgent is CVE-2020-7642?
Priority 39/100. Public exploit reference