VDB-354319 · CVE-2026-21861 · GHSA-qxmc-6f24-g86g

baserproject basercms up to 5.2.2 exec os command injection

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.8	$0-$5k	0.00

Summaryinfo

A vulnerability was found in baserproject basercms up to 5.2.2. It has been rated as critical. This impacts the function exec. This manipulation causes os command injection. The identification of this vulnerability is CVE-2026-21861. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in baserproject basercms up to 5.2.2. It has been declared as critical. Affected by this vulnerability is the function exec. The manipulation with an unknown input leads to a os command injection vulnerability. The CWE definition for the vulnerability is CWE-78. The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

baserCMS is a website development framework. Prior to version 5.2.3, baserCMS contains an OS command injection vulnerability in the core update functionality. An authenticated administrator can execute arbitrary OS commands on the server due to improper handling of user-controlled input that is directly passed to exec() without sufficient validation or escaping. This issue has been patched in version 5.2.3.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-21861 since 01/05/2026. The exploitation appears to be easy. The attack can be launched remotely. Additional levels of successful authentication are needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1202 according to MITRE ATT&CK.

Upgrading to version 5.2.3 eliminates this vulnerability. The upgrade is hosted for download at github.com.

The vulnerability is also documented in the vulnerability database at CNNVD (CNNVD-202603-6295). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Content Management System

Vendor

baserproject

Name

basercms

Version

License

open-source

Website

Product: https://github.com/baserproject/basercms/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.9
VulDB Meta Temp Score: 6.8

VulDB Base Score: 4.7
VulDB Temp Score: 4.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.1
CNA Vector (GitHub_M): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
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Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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

Exploitinginfo

Class: Os command injection
CWE: CWE-78 / CWE-77 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: basercms 5.2.3

Timelineinfo

01/05/2026 CVE reserved
03/31/2026 +84 days Advisory disclosed
03/31/2026 +0 days VulDB entry created
04/01/2026 +1 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-qxmc-6f24-g86g
Status: Confirmed

CVE: CVE-2026-21861 (🔒)
GCVE (CVE): GCVE-0-2026-21861
GCVE (VulDB): GCVE-100-354319
CNNVD: CNNVD-202603-6295 - baserCMS 安全漏洞

Entryinfo

Created: 03/31/2026 08:15
Updated: 04/01/2026 17:31
Changes: 03/31/2026 08:15 (67), 04/01/2026 17:31 (6)
Complete: 🔍
Cache ID: 216::103