CVE-2020-7777Arbitrary Code Execution
- 7.2HighCVSS base score
- 2.1%Exploitation in 30 daysEPSS · top 18% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
This affects all versions of package jsen. If an attacker can control the schema file, it could run arbitrary JavaScript code on the victim machine. In the module description and README file there is no mention about the risks of untrusted schema files, so I assume that this is applicable. In particular the required field of the schema is not properly sanitized. The resulting string that is build based on the schema definition is then passed to a Function.apply();, leading to an Arbitrary Code Execution.
Timeline
ID reserved
By snyk
- 10 months later
· 10 months later
Published
- 4 years later
· 4 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 |
|---|---|---|---|
| snykCNA (assigner) | 3.1 | High7.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:U/RC:C |
| NVDNVD · Modified | 3.1 | High7.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 2.1% · top 18% of all CVEs (12 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.2.
Affected products
jsen
- affected < unspecified
Affected packages
From reviewed advisories of the GitHub Advisory Database.
References
References2
- https://snyk.io/vuln/SNYK-JS-JSEN-1014670 (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/bugventure/jsen/blob/master/lib/jsen.js%23L875 (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-2022-1210 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-vm64-cfqx-3698 (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-2020-7777)Record last updated .