CVE-2021-37634

Leafkit is a templating language with Swift-inspired syntax. Versions prior to 1.3.0 are susceptible to Cross-site Scripting (XSS) attacks. This affects anyone passing unsanitised data to Leaf's variable tags. Before this fix, Leaf would not escape any strings passed to tags as variables. If an attacker managed to find a variable that was rendered with their unsanitised data, they could inject scripts into a generated Leaf page, which could enable XSS attacks if other mitigations such as a Content Security Policy were not enabled. This has been patched in 1.3.0. As a workaround sanitize any untrusted input before passing it to Leaf and enable a CSP to block inline script and CSS data.

CVSS v3 6.1 MEDIUM
CVSS v2.0 4.3 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

4.3^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:M/Au:N/C:N/I:P/A:N

Exploitability : 8.6 / Impact : 2.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact NONE

References

Link	Resource
https://github.com/vapor/leaf-kit-ghsa-rv3x-xq3r-8j9h/pull/1	Broken Link
https://github.com/vapor/leaf-kit/security/advisories/GHSA-rv3x-xq3r-8j9h	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:vapor:leafkit:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2021-08-09 20:15

Updated : 2024-02-28 18:28

NVD link : CVE-2021-37634

Mitre link : CVE-2021-37634

CVE.ORG link : CVE-2021-37634

JSON object : View

Products Affected

vapor

leafkit

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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