CVE-2021-26794

CRITICAL

Privilege escalation in 'upload.php' in FrogCMS SentCMS v0.9.5 allows attacker to execute arbitrary code via crafted php file.

Affects 1 product across 1 vendor.

CVSS 3.19.8
EPSS1.6%
Percentile75th
PatchUnknown
CVSS Vector — Plain English Remotely exploitable over the network, low complexity, no authentication required, no user interaction needed, impact contained to the vulnerable component, full confidentiality impact, full integrity impact, full availability impact.
CWE Weakness Definitions
CWE-434: Unrestricted Upload of File with Dangerous Type

Application allows file uploads without validating type, enabling upload of executable code or web shells.

Related Attack Patterns (CAPEC)
CAPEC-1 Accessing Functionality Not Properly Constrained by ACLs
via CWE-434

Mapping is CWE-to-CAPEC per MITRE CAPEC 3.9.

◆ AI Analysis — automated analysis, not human-reviewed

A critical vulnerability in FrogCMS SentCMS v0.9.5 allows attackers to escalate privileges and execute arbitrary code through a crafted PHP file uploaded via the 'upload.php' script.

BSID: BS-2021-GLOBAL-074553-C • Model: /workspace/models/qwen2.5-coder-32b-instruct-bf16 • Confidence: HIGH

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Frequently Asked Questions
What is CVE-2021-26794?
A critical vulnerability in FrogCMS SentCMS v0.9.5 allows attackers to escalate privileges and execute arbitrary code through a crafted PHP file uploaded via the 'upload.php' script.
What is the CVSS score for CVE-2021-26794?
CVE-2021-26794 has CVSS 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS: 1.6%.
Is CVE-2021-26794 actively exploited?
No confirmed active exploitation of CVE-2021-26794 as of 2026-05-30.
How do I remediate CVE-2021-26794?
Priority: IMMEDIATE.
What systems are affected by CVE-2021-26794?
CVE-2021-26794 affects Frog Cms Project Frogcms.
Vulnerability Details
CVE IDCVE-2021-26794
BSIDBS-2021-GLOBAL-074553-C BreachSpider Global ID
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published2021-09-23
Last Modified2024-11-21
ICS Relevance0%
Weakness (CWE)
Unrestricted Upload of File with Dangerous Type
SourceNVD
Official Description

Privilege escalation in 'upload.php' in FrogCMS SentCMS v0.9.5 allows attacker to execute arbitrary code via crafted php file.

Source: NIST NVD / MITRE CVE Database

Attack Vector Analysis — CITED Relevance

The vulnerability exists in the 'upload.php' script, which does not properly validate the uploaded file type and content. An attacker can exploit this by uploading a malicious PHP file, which can then be executed on the server, leading to arbitrary code execution and potential full system compromise.

Exploitation Likelihood: CRITICAL

Affected Products
VendorProductAffected Versions
Frog Cms Project Frogcms 0.9.5
Remediation

No official vendor advisory link on record. See the CVE record →

Threat Intelligence
● Threat Intelligence Validated: October 2026 | Threat Age: 1848 Days
CISA known-exploitedNot in KEV catalog
Public ExploitNot confirmed
PoC CodeNot confirmed
AI Enrichment Record — provenance & audit hash
Model/workspace/models/qwen2.5-coder-32b-instruct-bf16
ConfidenceHIGH
Enriched At2026-05-24
SHA-512 Audit Hash289879edd62980bce9c83a3714ca9a5eb0dc7ba578ac6328d65da1fb930b3ccd8bd91fae26cb8a0473c3342fd4ebf886a708fb46c99df9e4c20b50675b231201
Related CVEs affecting Frog Cms Project
CVE-2014-4912 9.8 An Arbitrary File Upload issue was discovered in Frog CMS 0.9.5 due to lack o... CVE-2018-8908 8.8 An issue was discovered in /admin/?/user/add in Frog CMS 0.9.5. The applicati... CVE-2024-42630 8.8 FrogCMS v0.9.5 was discovered to contain a Cross-Site Request Forgery (CSRF) ... CVE-2018-16447 8.8 Frog CMS 0.9.5 has admin/?/user/edit/1 CSRF. CVE-2024-42624 8.8 FrogCMS v0.9.5 was discovered to contain a Cross-Site Request Forgery (CSRF) ...
View all Frog Cms Project CVEs →

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