CVE-2026-9421
Published: 25 May 2026
Summary
CVE-2026-9421 is a medium-severity Improper Access Control (CWE-284) vulnerability. Its CVSS base score is 5.5 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 29.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-31624
Vulnerability details
A vulnerability was determined in KLiK SocialMediaWebsite 1.0. This vulnerability affects the function uniqid of the file upload.inc.php of the component File Handler. This manipulation causes unrestricted upload. The attack can be initiated remotely. The exploit has been publicly disclosed…
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and may be utilized.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Unrestricted file upload in a public-facing web application directly enables remote exploitation (T1190) and deployment of a web shell (T1505.003).
CVEs Like This One
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
This control enforces ownership-based restrictions on portable storage device use, directly implementing access control over media insertion into organizational systems.
Hardware write-protect enforces access control on critical resources (e.g., firmware) independent of software state.
The access control policy and procedures directly mandate and enforce proper access control mechanisms across the organization.
Device lock enforces restricted access until re-authentication, directly reducing unauthorized use of active sessions.
Supervision and review of access control activities directly detects and remediates improper access configurations or usages.
Explicitly identifying and documenting actions permitted without identification or authentication enforces proper access control boundaries by defining justified exceptions.
By automatically labeling outputs with security attributes, the control supports attribute-based enforcement and reduces exploitability of improper access control weaknesses.
Associating and retaining security attributes with data directly supports enforcement of access control decisions across storage, processing, and transmission.