NYUCCL psiTurk up to 3.2.0 psiturk/experiment.py mode special elements used in a template engine

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability has been found in NYUCCL psiTurk up to 3.2.0 and classified as critical. This vulnerability affects some unknown functionality of the file psiturk/experiment.py. The manipulation of the argument mode with an unknown input leads to a improper neutralization of special elements used in a template engine vulnerability. The CWE definition for the vulnerability is CWE-1336. The product uses a template engine to insert or process externally-influenced input, but it does not neutralize or incorrectly neutralizes special elements or syntax that can be interpreted as template expressions or other code directives when processed by the engine. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was released 01/27/2023 as 517. The advisory is shared for download at github.com. This vulnerability was named CVE-2021-4315. Technical details and also a public exploit are known. The MITRE ATT&CK project declares the attack technique as T1221.

It is possible to download the exploit at github.com. It is declared as proof-of-concept.

Upgrading to version 3.2.1 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 47787e15cecd66f2aa87687bf852ae0194a4335f is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version. The advisory contains the following remark:

Fixed an issue where users could pass arbitrary Python code to be executed on the server to the mode HTTP arg





  • open-source

CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 6.6
VulDB Meta Temp Score: 6.4

VulDB Base Score: 5.5
VulDB Temp Score: 5.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔒

CNA Base Score: 5.5
CNA Vector (VulDB): 🔒



VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

NVD Base Score: 🔒


Class: Improper neutralization of special elements used in a template engine
CWE: CWE-1336 / CWE-791 / CWE-790
ATT&CK: T1221

Local: No
Remote: Partially

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒


Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: psiTurk 3.2.1
Patch: 47787e15cecd66f2aa87687bf852ae0194a4335f


01/27/2023 Advisory disclosed
01/27/2023 +0 days CVE reserved
01/27/2023 +0 days VulDB entry created
02/23/2023 +27 days VulDB last update


Advisory: 517
Status: Confirmed

CVE: CVE-2021-4315 (🔒)
scip Labs: https://www.scip.ch/en/?labs.20161013


Created: 01/27/2023 11:47 PM
Updated: 02/23/2023 06:25 PM
Changes: 01/27/2023 11:47 PM (48), 02/23/2023 06:18 PM (2), 02/23/2023 06:25 PM (28)
Complete: 🔍


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