Cyber Resilience

CVE-2023-28731

CriticalPublic PoC

Published: 30 March 2023

Published
30 March 2023
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0906 92.8th percentile
Risk Priority 25 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-28731 is a critical-severity Improper Input Validation (CWE-20) vulnerability in Acymailing Acymailing. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 7.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis

The vulnerability is an unauthenticated remote code execution flaw in the AnyMailing Joomla Plugin Enterprise edition, caused by unrestricted file upload that permits injection of PHP code. It affects all versions below 8.3.0 and stems from improper input validation (CWE-20) combined with acceptance of dangerous file types (CWE-434). The issue manifests when an attacker is granted access to campaign creation functionality exposed on the front office.

An attacker can exploit the flaw over the network without authentication or user interaction to upload and execute arbitrary PHP payloads. Successful exploitation grants full control over the affected Joomla instance, allowing arbitrary code execution with impacts to confidentiality, integrity, and availability, consistent with the CVSS 9.8 rating.

Public advisories and the vendor change log recommend upgrading to version 8.3.0 or later to remediate the unrestricted upload condition. The EPSS score has remained flat at 0.0906 with no material increase since disclosure.

EU & UK References

Vulnerability details

AnyMailing Joomla Plugin is vulnerable to unauthenticated remote code execution, when being granted access to the campaign's creation on front-office due to unrestricted file upload allowing PHP code to be injected. This issue affects AnyMailing Joomla Plugin Enterprise in versions…

more

below 8.3.0.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

acymailing
acymailing
≤ 8.3.0

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.

addresses: CWE-434

Requiring identifiable owners for portable devices reduces the attack surface for unrestricted uploads of dangerous file types via anonymous media.

addresses: CWE-20

Security testing and developer training directly verify and enforce proper input validation, reducing exploitability of injection and malformed-data weaknesses.

addresses: CWE-20

Security testing and evaluation at multiple SDLC stages directly detects missing or flawed input validation, with the required remediation process ensuring fixes are applied.

addresses: CWE-434

Dangerous file uploads can be detonated in the chamber to determine malice before any production write or execution occurs.

addresses: CWE-434

Prevents unrestricted writing of arbitrary or malicious firmware by keeping hardware write-protect enabled except under tightly controlled manual procedures.

addresses: CWE-20

Directly implements checks on information inputs to reject invalid data before processing.

addresses: CWE-434

Scans files from external sources on download/open/execute, blocking unrestricted uploads of dangerous file types.

addresses: CWE-20

Spam protection mechanisms perform filtering and detection on inbound/outbound messages, directly compensating for missing or weak input validation of unsolicited content.

References