# CVE-2026-48939: iCagenda Unrestricted Upload of File with Dangerous Type

> Attackers can upload arbitrary PHP files via the attachment feature to execute remote code on Joomla sites using the iCagenda extension.

- **Severity:** Critical 10.0 (`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:A/AU:Y/U:Red`)
- **Exploited in the wild:** Yes, since 10 Jul 2026 (CISA KEV)
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 20 Jun 2026
- **Updated:** 12 Aug 2026
- **Also known as:** GHSA-4rh3-rmh3-hv6h

## What is CVE-2026-48939?

CVE-2026-48939 is a critical vulnerability in icagenda.com iCagenda extension for Joomla, published on 20 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the iCagenda extension for Joomla allows the upload of arbitrary files in the file attachment feature, ultimately resulting in PHP code upload and execution.

Weakness: CWE-434 (Unrestricted Upload of File with Dangerous Type)

## Which versions are affected by CVE-2026-48939?

It affects 1 product.


Products: Joomlic Icagenda.

## How do I fix CVE-2026-48939?

No fix has been published for CVE-2026-48939 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 13 Jul 2026.

## Is CVE-2026-48939 being exploited?

Yes. Attackers have exploited CVE-2026-48939 in the wild since at least 10 Jul 2026.

Public exploit code:

- Pre-auth arbitrary file upload RCE exploit for iCagenda Joomla extension < 4.0.8 (CVSS 10.0) (github_poc): https://github.com/shinthink/CVE-2026-48939
- iCagenda Unauthenticated File Upload to RCE (github_poc): https://github.com/Polosss/By-Poloss..-..CVE-2026-48939
- iCagenda extension for Joomla allows the upload of arbitrary files in the file attachment feature, ultimately resulting in PHP code upload and execution. (github_poc): https://github.com/ChiefYoru/CVE-2026-48939_PoC
- Joomla iCagenda < 3.9.10 - Unauthenticated Arbitrary File Upload RCE (nuclei): http/cves/2026/CVE-2026-48939.yaml

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-48939 and fix it if it is affected.

What it is: CVE-2026-48939 is a critical vulnerability in icagenda.com iCagenda extension for Joomla, published on 20 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2026-48939 in the wild since at least 10 Jul 2026.

Affected product: icagenda.com iCagenda extension for Joomla. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-48939/ (Markdown: https://insights.sbomify.com/CVE-2026-48939/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-48939
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-48939
- OSV: https://osv.dev/vulnerability/CVE-2026-48939

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-48939/
Summaries are generated and may contain mistakes; the official description above is the record.