Cyber Resilience

CVE-2026-56291

Balbooa Forms ≤ 2.4.1

CISA KEVActive ExploitationEUVD ExploitedPublic PoC
Published
09 July 2026
Modified
24 July 2026
KEV Added
10 July 2026
Patch / advisory
CVSS Score v4 10.0
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:A/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:X/RE:X/U:Red
EPSS Score 0.76 99.5th percentile
Risk Priority 80 floored blend · peak EPSS

Summary

CVE-2026-56291 is a critical-severity Unrestricted Upload of File with Dangerous Type (CWE-434) vulnerability in Balbooa Forms. Its CVSS base score is 10.0 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 0.5% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Joomla Extension - balbooa.com - Unauthenticated file upload in Balbooa Forms extension < 2.4.1 - The Joomla extension Balbooa Forms is vulnerable to an unauthenticated arbitrary file upload that allows uploading executable files and leads to full RCE.

CWE(s)
KEV Date Added
10 July 2026

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1105 Ingress Tool Transfer Command And Control
Adversaries may transfer tools or other files from an external system into a compromised environment.
T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
Why these techniques?

Unauthenticated arbitrary file upload (CWE-434) in a public-facing Joomla extension directly enables remote code execution via malicious file upload (T1190), followed by tool transfer (T1105) and command/script execution (T1059) on the compromised server.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

Likely ATT&CK TechniquesAI

Techniques this vulnerability likely enables, inferred from its description, weakness type, and attributed-actor tradecraft. Confidence is per-technique.

T1190 Exploit Public-Facing Application Initial Accessconfidence: HIGH
Unauthenticated arbitrary file upload to a public-facing Joomla web application directly enables remote code execution via malicious file upload.
T1505.003 Web Shell Persistenceconfidence: HIGH
Arbitrary upload of executable files to a web server facilitates deployment of a web shell for persistent remote access.
T1059 Command and Scripting Interpreter Executionconfidence: MEDIUM
Successful RCE via uploaded executable allows execution of arbitrary commands on the compromised host.
inferred from description + CWE · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2025-52691Shared CWE-434both on KEV
CVE-2026-48939Shared CWE-434both on KEV
CVE-2026-56290Shared CWE-434both on KEV
CVE-2026-48908Shared CWE-434both on KEV
CVE-2024-57968Shared CWE-434both on KEV
CVE-2024-39717Shared CWE-434both on KEV
CVE-2021-26828Shared CWE-434both on KEV
CVE-2021-27860Shared CWE-434both on KEV
CVE-2018-4063Shared CWE-434both on KEV
CVE-2024-7694Shared CWE-434both on KEV

Affected Assets

balbooa
forms
≤ 2.4.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-10 Information Input Validation
  • AC-3 Access Enforcement
  • SI-3 Malicious Code Protection
Detect
Catch it (NIST detect / respond)
  • SI-3 Malicious Code Protection
Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V5.1.1

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces validation of uploaded file types and content to block executable files (CWE-434).

prevent

Requires authentication and authorization checks before permitting any file upload operations.

preventdetect

Scans incoming files for malicious code before they are stored or executed on the server.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-05 mostly match
prevents

Restricting execution of unauthorized software directly blocks dangerous uploaded files from running.

PR.PS-01 partial match
prevents

Hardened configuration baselines can enforce allowed file types and processing rules.

PR.PS-06 partial match
prevents

Secure development practices include input validation and file-type restrictions that prevent this weakness.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Configuration and acceptance testing verify that file-upload handling enforces allowed types and does not permit dangerous content to be stored or executed.

prevents

Secure-coding guidelines and security testing explicitly address restrictions on allowed file types and upload handling, reducing the risk that dangerous file uploads are accepted without validation.

prevents

Mandated testing for malicious content and known vulnerabilities reduces the likelihood that an outsourced component will contain or accept dangerous file types that could later be uploaded or executed.

mitigates

Application allow-listing and pre-use scanning of received files directly blocks the introduction of executable content that has not been vetted, eliminating the primary vector for unrestricted dangerous file uploads.

References