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Online Reviewer System CVE-2021-41646

CRITICAL
Unrestricted Upload of File with Dangerous Type (CWE-434)
2021-10-29 cve@mitre.org
9.8
CVSS 3.1 · NVD
View

Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V5 - File Handling File type validation, storage isolation
MITRE ATT&CK

2 techniques across 2 tactics: Command and Control, Persistence

The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up.

Impact

CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available. EPSS exploitation probability: 3.68%.

Exploit ScenarioDerived

A remote attacker could upload malicious files that can be executed on the server by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability.

Act Now Prioritize within 24-48h. Why: CRITICAL severity + public POC available.
No patch listed yet 3.7% exploitation probability (EPSS)

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AnalysisAI

Remote Code Execution (RCE) vulnerability exists in Sourcecodester Online Reviewer System 1.0 by uploading a maliciously crafted PHP file that bypasses the image upload filters.. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Validate file types server-side, store uploads outside webroot, use random filenames, scan for malware.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified as Unrestricted File Upload (CWE-434), which allows attackers to upload malicious files that can be executed on the server. Remote Code Execution (RCE) vulnerability exists in Sourcecodester Online Reviewer System 1.0 by uploading a maliciously crafted PHP file that bypasses the image upload filters.. Affected products include: Janobe Online Reviewer System.

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  • Exploit and PoC references, threat intelligence from 22 sources

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Severity by source

NVD PRIMARY 9.8 CRITICAL
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

DescriptionCVE.org

Remote Code Execution (RCE) vulnerability exists in Sourcecodester Online Reviewer System 1.0 by uploading a maliciously crafted PHP file that bypasses the image upload filters..

Threat Intelligence Overview

EPSS Score
3.7%
Top 12% exploitable
Exploit
POC
Public exploit code exists
Data Quality
5 sources
Confidence: Medium
NVD CVE.org EPSS Exploit-DB VulDB

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity CRITICAL
CISA KEV No
Public POC Yes
EPSS 3.7%
Patch available No
Active threat No
Deciding rule
CRITICAL severity + public POC available
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
Poc
System Exposure· derived
Open
Automatable· derived
Yes
Human Impact· derived
Medium

Priority Score

73
Low Medium High Critical
KEV: 0
EPSS: +4
CVSS: +49
PoC: +20
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Malicious file upload attacks exploit insufficient validation when web applications accept user-provided files.

Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.

Affected Products (CPE)CVE.org

cpe:2.3:a:janobe:online_reviewer_system:1.0:*:*:*:*:*:*:*
CVE-2021-27130 CRITICAL POC
9.8 Apr 14

Online Reviewer System 1.0 contains a SQL injection vulnerability through authentication bypass, which may lead to a rev

CVE-2023-2596 MEDIUM POC
6.3 May 09

A vulnerability was found in SourceCodester Online Reviewer System 1.0 and classified as critical. Rated medium severity

CVE-2026-109620 MEDIUM POC
5.5 Oct 13

SQL injection in SourceCodester Online Reviewer System 1.0 allows unauthenticated remote attackers to alter the SQL quer

CVE-2026-2166 MEDIUM POC
5.5 Feb 08

SQL injection in the Online Reviewer System 1.0 login function allows unauthenticated remote attackers to manipulate use

CVE-2026-2195 MEDIUM POC
5.5 Feb 09

SQL injection in code-projects Online Reviewer System 1.0 via the ID parameter in the questions-view.php file allows una

CVE-2026-2912 MEDIUM POC
5.5 Feb 22

SQL injection in Online Reviewer System 1.0 allows unauthenticated remote attackers to manipulate the test_id parameter

CVE-2026-2221 MEDIUM POC
5.5 Feb 09

SQL injection in the login component of code-projects Online Reviewer System 1.0 allows unauthenticated remote attackers

CVE-2026-2220 MEDIUM POC
5.5 Feb 09

SQL injection in code-projects Online Reviewer System 1.0 via the difficulty_id parameter in /system/system/admins/asses

CVE-2026-2199 MEDIUM POC
5.5 Feb 09

SQL injection in code-projects Online Reviewer System 1.0 allows unauthenticated remote attackers to manipulate the ID p

CVE-2026-2198 MEDIUM POC
5.5 Feb 09

SQL injection in code-projects Online Reviewer System 1.0 via the difficulty_id parameter in /system/system/admins/asses

CVE-2026-2197 MEDIUM POC
5.5 Feb 09

SQL injection in code-projects Online Reviewer System 1.0 allows remote attackers to manipulate the test_id parameter in

CVE-2026-2196 MEDIUM POC
5.5 Feb 09

SQL injection in code-projects Online Reviewer System 1.0 allows unauthenticated remote attackers to manipulate the test

References

Advisories & patches

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