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CVE-2021-3783Cross-site Scripting (XSS) - Reflected in yourls/yourls
- 6.6MediumCVSS base score
- 0.70%Exploitation in 30 daysEPSS · top 46% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
yourls is vulnerable to Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Timeline
ID reserved
By @huntrdev
- 6 days later
· 6 days later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| @huntrdevCNA (assigner) | 3.0 | Medium6.6 | CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Medium6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.70% · top 46% of all CVEs (14 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.6.
Affected products
- affected unspecified – ≤ 1.8.2
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Packagistyourls/yourlsGHSA-cpq8-x35g-m439 (opens in a new tab)
References
References2
- https://huntr.dev/bounties/b688e553-d0d9-4ddf-95a3-ff4b78004984 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/yourls/yourls/commit/94f6bab91182142c96ff11f481585b445449efd4 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2021-2041 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-cpq8-x35g-m439 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2021-3783)Record last updated .