CVE-2021-41170

neoan3-apps/template is a neoan3 minimal template engine. Versions prior to 1.1.1 have allowed for passing in closures directly into the template engine. As a result values that are callable are executed by the template engine. The issue arises if a value has the same name as a method or function in scope and can therefore be executed either by mistake or maliciously. In theory all users of the package are affected as long as they either deal with direct user input or database values. A multi-step attack on is therefore plausible. Version 1.1.1 has addressed this vulnerability. Unfortunately only working with hardcoded values is safe in prior versions. As this likely defeats the purpose of a template engine, please upgrade.
Configurations

Configuration 1 (hide)

cpe:2.3:a:neoan:neoan3-template:*:*:*:*:*:*:*:*

History

17 Nov 2021, 13:16

Type Values Removed Values Added
Summary ### Impact Versions prior 1.1.1 have allowed for passing in closures directly into the template engine. As a result values that are callable are executed by the template engine. The issue arises if a value has the same name as a method or function in scope and can therefore be executed either by mistake or maliciously. In theory all users of the package are affected as long as they either deal with direct user input or database values. A multi-step attack on is therefore plausible. ### Patches Version 1.1.1 has addressed this vulnerability. ```php $params = [ 'reverse' => fn($input) => strrev($input), // <-- no longer possible with version ~1.1.1 'value' => 'My website' ] TemplateFunctions::registerClosure('reverse', fn($input) => strrev($input)); // <-- still possible (and nicely isolated) Template::embrace('<h1>{{reverse(value)}}</h1>', $params); ``` ### Workarounds Unfortunately only working with hardcoded values is safe in prior versions. As this likely defeats the purpose of a template engine, please upgrade. ### References As a possible exploit is relatively easy to achieve, I will not share steps to reproduce the issue for now. ### For more information If you have any questions or comments about this advisory: * Open an issue in [our repo](https://github.com/sroehrl/neoan3-template) neoan3-apps/template is a neoan3 minimal template engine. Versions prior to 1.1.1 have allowed for passing in closures directly into the template engine. As a result values that are callable are executed by the template engine. The issue arises if a value has the same name as a method or function in scope and can therefore be executed either by mistake or maliciously. In theory all users of the package are affected as long as they either deal with direct user input or database values. A multi-step attack on is therefore plausible. Version 1.1.1 has addressed this vulnerability. Unfortunately only working with hardcoded values is safe in prior versions. As this likely defeats the purpose of a template engine, please upgrade.
CWE CWE-732 CWE-277
CWE-74

13 Nov 2021, 04:08

Type Values Removed Values Added
CVSS v2 : unknown
v3 : 7.5
v2 : 7.5
v3 : 9.8
CPE cpe:2.3:a:neoan:neoan3-template:*:*:*:*:*:*:*:*
CWE CWE-277 CWE-732
References (CONFIRM) https://github.com/sroehrl/neoan3-template/security/advisories/GHSA-3v56-q6r6-4gcw - (CONFIRM) https://github.com/sroehrl/neoan3-template/security/advisories/GHSA-3v56-q6r6-4gcw - Patch, Third Party Advisory
References (MISC) https://github.com/sroehrl/neoan3-template/commit/4a2c9570f071d3c8f4ac790007599cba20e16934 - (MISC) https://github.com/sroehrl/neoan3-template/commit/4a2c9570f071d3c8f4ac790007599cba20e16934 - Patch, Third Party Advisory
References (MISC) https://github.com/sroehrl/neoan3-template/issues/8 - (MISC) https://github.com/sroehrl/neoan3-template/issues/8 - Issue Tracking, Patch, Third Party Advisory

08 Nov 2021, 20:15

Type Values Removed Values Added
New CVE

Information

Published : 2021-11-08 19:15

Updated : 2023-12-10 14:09


NVD link : CVE-2021-41170

Mitre link : CVE-2021-41170

CVE.ORG link : CVE-2021-41170


JSON object : View

Products Affected

neoan

  • neoan3-template
CWE
CWE-277

Insecure Inherited Permissions

CWE-74

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

CWE-732

Incorrect Permission Assignment for Critical Resource