CMSimple 5.4 Template Editing Endpoint code injection

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability was found in CMSimple 5.4 and classified as critical. This issue affects some unknown processing of the component Template Editing Endpoint. Such manipulation leads to code injection. This vulnerability is referenced as CVE-2021-47735. It is possible to launch the attack remotely. Furthermore, an exploit is available.

Detailsinfo

A vulnerability, which was classified as critical, has been found in CMSimple 5.4. Affected by this issue is an unknown code of the component Template Editing Endpoint. The manipulation with an unknown input leads to a code injection vulnerability. Using CWE to declare the problem leads to CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. Impacted is confidentiality, integrity, and availability. CVE summarizes:

CMSimple 5.4 contains an authenticated remote code execution vulnerability that allows logged-in attackers to inject malicious PHP code into template files. Attackers can exploit the template editing functionality by crafting a reverse shell payload and saving it through the template editing endpoint with a valid CSRF token.

The weakness was published by pussycat0x as 50356. The advisory is shared for download at exploit-db.com. This vulnerability is handled as CVE-2021-47735 since 12/23/2025. The exploitation is known to be easy. The attack may be launched remotely. Technical details are unknown but a public exploit is available. The MITRE ATT&CK project declares the attack technique as T1059.

The exploit is available at exploit-db.com. It is declared as proof-of-concept.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Exploit-DB (50356). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.2

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.8
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Code injection
CWE: CWE-94 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

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

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Exploit-DB: 🔒

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

12/23/2025 Advisory disclosed
12/23/2025 +0 days CVE reserved
12/23/2025 +0 days VulDB entry created
12/23/2025 +0 days VulDB entry last update

Sourcesinfo

Advisory: 50356
Researcher: pussycat0x
Status: Not defined

CVE: CVE-2021-47735 (🔒)
GCVE (CVE): GCVE-0-2021-47735
GCVE (VulDB): GCVE-100-337880
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 12/23/2025 22:21
Changes: 12/23/2025 22:21 (79)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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