CVE-2026-21625VulnerabilityPublished 16 Jan 2026

CVE-2026-21625: Stackideas.com EasyDiscuss extension for Joomla · Unrestricted File Upload

Affects Stackideas.com EasyDiscuss extension for JoomlaSource CVE Database V5

Not known to be exploited · CVSS 4.8 Medium.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 4.0 base score

4.8Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 32% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:L

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: Low
User Interaction: Active
Vulnerable system confidentiality: None
Vulnerable system integrity: None
Vulnerable system availability: None
Subsequent system confidentiality: Low
Subsequent system integrity: Low
Subsequent system availability: Low

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: Low: The attacker requires privileges that provide basic capabilities that are typically limited to settings and resources owned by a single low-privileged user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.
User Interaction: Active: Successful exploitation of this vulnerability requires a targeted user to perform specific, conscious interactions with the vulnerable system and the attacker’s payload, or the user’s interactions would actively subvert protection mechanisms which would lead to exploitation of the vulnerability.
Vulnerable system confidentiality: None: There is no loss of confidentiality within the Vulnerable System.
Vulnerable system integrity: None: There is no loss of integrity within the Vulnerable System.
Vulnerable system availability: None: There is no impact to availability within the Vulnerable System.
Subsequent system confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the Subsequent System.
Subsequent system integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact to the Subsequent System.
Subsequent system availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the Subsequent System are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the Subsequent System.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 16 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Stackideas.comEasyDiscuss extension for Joomla	Affected =1.0.0-5.0.15	Fixed in–

AI-suggested

1. Immediately restrict file upload capabilities in EasyDiscuss to trusted users only, or disable uploads if not essential. 2. Implement server-side validation that checks both file extensions and MIME types to ensure only safe file types are accepted. 3. Use file content inspection tools or antivirus scanning on uploaded files to detect malicious payloads. 4. Apply web application firewall (WAF) rules to detect and block suspicious upload attempts targeting EasyDiscuss endpoints. 5. Monitor logs for unusual upload activity or errors related to file handling. 6. Keep Joomla and all extensions updated; apply vendor patches promptly once released. 7. Educate users about the risks of uploading files and enforce strict upload policies. 8. Consider isolating upload directories with restrictive permissions and disabling script execution in those directories. 9. Regularly audit and test the upload functionality for security weaknesses. 10. If possible, employ Content Security Policy (CSP) headers to limit the impact of any malicious scripts that might be uploaded.

Description

User provided uploads to the Easy Discuss component for Joomla aren't properly validated. Uploads are purely checked by file extensions, no mime type checks are happening.

Impact

For European organizations using Joomla with the EasyDiscuss extension, this vulnerability could lead to unauthorized file uploads that enable attackers to execute malicious scripts, deface websites, or gain further access to internal systems. This could result in data breaches, service disruptions, reputational damage, and compliance violations under GDPR if personal data is compromised. Organizations running community forums or customer support portals with EasyDiscuss are particularly at risk. The medium CVSS score indicates a moderate risk, but the potential for chained attacks or privilege escalation after initial compromise could amplify the impact. Since Joomla is popular in several European countries, especially Germany, France, and the UK, organizations in these regions with active Joomla deployments are more exposed. The vulnerability could also be leveraged to distribute malware or conduct phishing campaigns via compromised websites. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially as attackers often develop exploits after public disclosure.

Summary

CVE-2026-21625 is a vulnerability classified under CWE-434 (Unrestricted Upload of File with Dangerous Type) affecting the EasyDiscuss extension for Joomla versions 1.0.0 through 5.0.15. The core issue lies in the insufficient validation of user-uploaded files: the extension only checks the file extension but does not verify the MIME type or perform deeper content inspection. This allows attackers to upload files with dangerous content disguised under allowed extensions, potentially leading to remote code execution, website defacement, or unauthorized access if the uploaded files are processed or executed by the server. The vulnerability has a CVSS 4.8 (medium) score, reflecting that it can be exploited remotely over the network with low attack complexity and no privileges required, but it does require user interaction (e.g., tricking a user to upload a malicious file). No known exploits are currently reported in the wild, but the risk remains significant due to the widespread use of Joomla and EasyDiscuss for community forums and discussion boards. The lack of MIME type validation is a common security oversight that can be exploited to bypass extension-based filters. The vulnerability's impact is limited by the need for user interaction and the absence of privilege escalation or direct authentication bypass, but it can still lead to serious consequences if exploited. The vendor has not yet provided patches, so mitigation relies on configuration changes and monitoring.

CWE-434Unrestricted Upload of File with Dangerous Type (opens in a new tab)
Base weaknessLikelihood of exploit: MediumCWE Top 25 (2025): #12OWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.
Architecture and Design
Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.
Architecture and Design · Enforcement by Conversion
When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
Architecture and Design
Consider storing the uploaded files outside of the web document root entirely. Then, use other mechanisms to deliver the files dynamically.
OWASP Cheat Sheets
Server Side Request Forgery Prevention (opens in a new tab)
Web Service Security (opens in a new tab)
Third Party Javascript Management (opens in a new tab)
File Upload (opens in a new tab)
Secure Design Principles (opens in a new tab)
OWASP ASVS 4.0.3
V12.5.2 (opens in a new tab)
V13.1.5 (opens in a new tab)
V12.2.1 (opens in a new tab)
Attack patterns
Accessing Functionality Not Properly Constrained by ACLs (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

stackideas.com/easydiscuss (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 16 Jan 2026, 15:36 UTC

WeaknessesCWE-434

Technical details

References

Community reviews

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