Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Attack requirements (AT:N) | No attack requirements |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Confidentiality (VC:H) | High confidentiality impact |
| Integrity (VI:H) | High integrity impact |
| Availability (VA:H) | High availability impact |
CVSS: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:X/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:X/R:X/V:X/RE:X/U:X
About Aimy-Extensions Aimy Captcha-Less Form Guard
CVE-2026-65883 affects Aimy-Extensions Aimy Captcha-Less Form Guard, a product from Aimy-Extensions. Before acting, confirm where Aimy-Extensions Aimy Captcha-Less Form Guard runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: Joomla Extension - aimy-extensions.com - RCE via PHP object injection in Aimy Captcha-Less Form Guard 18.0 - 20.0 - A forged clfgd field allows PHP objection injection and thereby remote code execution.
The weakness class is Deserialization of Untrusted Data. The application rebuilds objects from attacker controlled data, which can run code.
Based on its CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Aimy-Extensions Aimy Captcha-Less Form Guard |
| Affected versions | Aimy Captcha-Less Form Guard from 18.0 up to and including 20.0 |
| Published | Jul 29, 2026 |
| Last modified | Aug 5, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | security@joomla.org |
How to detect it
- Inventory every instance of Aimy-Extensions Aimy Captcha-Less Form Guard and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Aimy-Extensions Aimy Captcha-Less Form Guard named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Aimy-Extensions Aimy Captcha-Less Form Guard to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-502: Deserialization of Untrusted Data More CVEs with this weakness
Technical References
Frequently asked questions
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