High severity · published Sep 30, 2020
CVE-2019-20920
Handlebars before 3.0.8 and 4.x before 4.5.3 is vulnerable to Arbitrary Code Execution
8.1
CVSS
3.2%
EPSS
No
On KEV
Description
Handlebars before 3.0.8 and 4.x before 4.5.3 is vulnerable to Arbitrary Code Execution. The lookup helper fails to properly validate templates, allowing attackers to submit templates that execute arbitrary JavaScript. This can be used to run arbitrary code on a server processing Handlebars templates or in a victim's browser (effectively serving as XSS).
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:L
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
Low
Availability
Low
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)3.2% · higher than 88% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HA
Handlebars · Handlebarsjs
before 3.0.8; 4.0.0 before 4.5.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-20920
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-20920
Third Party Advisory
https://snyk.io/vuln/SNYK-JS-HANDLEBARS-534478
Exploit
https://www.npmjs.com/advisories/1316
Third Party Advisory
https://www.npmjs.com/advisories/1324
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