# CVE-2026-91849: WuzhiCMS Avatar Upload index.php setAvatar unrestricted upload

> Attackers can upload malicious files via the avatar upload feature in WuzhiCMS, potentially leading to remote code execution.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Sep 2026
- **Updated:** 17 Sep 2026
- **Also known as:** GHSA-rhh7-mmrm-695f

## What is CVE-2026-91849?

CVE-2026-91849 is a medium-severity vulnerability in WuzhiCMS, published on 15 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A security flaw has been discovered in WuzhiCMS up to 4.1.0. This affects the function member::setAvatar of the file /index.php?m=member&f=user&v=setAvatar of the component Avatar Upload. The manipulation of the argument File results in unrestricted upload. The attack can be executed remotely. The exploit has been released to the public and may be used for attacks. The project was informed of the problem early through an issue report but has not responded yet.

Weakness: CWE-434 (Unrestricted Upload of File with Dangerous Type), CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2026-91849?


## How do I fix CVE-2026-91849?

No fix has been published for CVE-2026-91849 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-91849 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-91849 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-91849 and fix it if it is affected.

What it is: CVE-2026-91849 is a medium-severity vulnerability in WuzhiCMS, published on 15 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-91849 exists.

Affected product: WuzhiCMS. 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-2026-91849/ (Markdown: https://insights.sbomify.com/CVE-2026-91849/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-91849
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-91849
- OSV: https://osv.dev/vulnerability/CVE-2026-91849

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-91849/
Summaries are generated and may contain mistakes; the official description above is the record.