CVE-2019-20920: 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…

PriorityP347high8.1CVSS 3.1

AVNACHPRNUINSCCHILAL

EPSS

3.19%

86.5th percentile

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).

Affected

5 ranges

Vendor	Product	Version range	Fixed in
debian	node-handlebars	< node-handlebars 3:4.5.3-1 (bookworm)	node-handlebars 3:4.5.3-1 (bookworm)
handlebarsjs	handlebars	< 3.0.8	3.0.8
handlebarsjs	handlebars	>= 0 < 3.0.8	3.0.8
handlebarsjs	handlebars	>= 4.0.0 < 4.5.3	4.5.3
handlebarsjs	handlebars	>= 4.0.0 < 4.5.3	4.5.3

CVSS provenance

nvdv3.18.1HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:L

nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P

osv8.1HIGH

vendor_debian8.1HIGH

vendor_redhat8.1HIGH

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