# CVE-2023-49105: ownCloud Improper Authentication

> Attackers can access, modify, or delete files without authentication if the victim lacks a signing key, affecting ownCloud server deployments.

- **Severity:** Critical 9.8 (`CVSS:3.1/AC:L/AV:N/A:H/C:H/I:H/PR:N/S:U/UI:N`)
- **Exploited in the wild:** Yes, since 27 Aug 2026 (CISA KEV)
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 21 Nov 2023
- **Updated:** 28 Aug 2026
- **Also known as:** GHSA-585g-f852-v6p4

## What is CVE-2023-49105?

CVE-2023-49105 is a critical authentication bypass vulnerability in Owncloud Owncloud Server, published on 21 Nov 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An issue was discovered in ownCloud owncloud/core before 10.13.1. An attacker can access, modify, or delete any file without authentication if the username of a victim is known, and the victim has no signing-key configured. This occurs because pre-signed URLs can be accepted even when no signing-key is configured for the owner of the files. The earliest affected version is 10.6.0.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2023-49105?

It affects 1 product.


Products: Owncloud Owncloud Server.

## How do I fix CVE-2023-49105?

No fix has been published for CVE-2023-49105 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 30 Aug 2026.

## Is CVE-2023-49105 being exploited?

Yes. Attackers have exploited CVE-2023-49105 in the wild since at least 27 Aug 2026.

Public exploit code:

- ownCloud exploits for CVE-2023-49105 (github_poc): https://github.com/ambionics/owncloud-exploits

## Other vulnerabilities in Owncloud Owncloud Server

- [CVE-2015-7699](https://insights.sbomify.com/CVE-2015-7699/): Code injection in n/a (critical 9.0)
- [CVE-2015-6500](https://insights.sbomify.com/CVE-2015-6500/): Path traversal in n/a (high 7.5)
- [CVE-2014-2051](https://insights.sbomify.com/CVE-2014-2051/): Code injection in n/a (high 7.5)
- [CVE-2014-2054](https://insights.sbomify.com/CVE-2014-2054/): PHPExcel vulnerable to XXE attacks through libxml (high 7.5)
- [CVE-2014-2056](https://insights.sbomify.com/CVE-2014-2056/): XML external entity in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-49105 and fix it if it is affected.

What it is: CVE-2023-49105 is a critical authentication bypass vulnerability in Owncloud Owncloud Server, published on 21 Nov 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2023-49105 in the wild since at least 27 Aug 2026.

Affected product: Owncloud Owncloud Server. 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-2023-49105/ (Markdown: https://insights.sbomify.com/CVE-2023-49105/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-49105
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-49105
- OSV: https://osv.dev/vulnerability/CVE-2023-49105

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-49105/
Summaries are generated and may contain mistakes; the official description above is the record.