PatchTheCVECVE-2021-34364: The Refined GitHub browser extension before 21.6.8 might allow XSS via a link in a document
CVE-2021-34364 is a medium-severity flaw (CVSS 6.1) affecting refined-github. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
The Refined GitHub browser extension before 21.6.8 might allow XSS via a link in a document. NOTE: github.com sends Content-Security-Policy headers to, in general, address XSS and other concerns.
Why this priority
- No elevated risk signals yet
A fixed release or distro patch exists.
Risk facts
| CVSS score | 6.1 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | Required |
| EPSS exploit chance | 0.7% (top 47%) |
| CISA exploited list | No |
| Weakness | CWE-79 |
| Published | 2021-06-09 |
| 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-2021-34364?
refined-github: upgrade to 21.6.8. Exact commands for each OS are on this page.
Is CVE-2021-34364 being exploited?
CVE-2021-34364 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-2021-34364 affect?
CVE-2021-34364 affects refined-github. Severity is medium (CVSS 6.1). The Refined GitHub browser extension before 21.6.8 might allow XSS via a link in a document. NOTE: github.com sends Content-Security-Policy headers to, in general, address XSS and other concerns.
How urgent is CVE-2021-34364?
Priority 34/100. No elevated risk signals yet.