# CVE-2026-49248: OneDev arbitrary file write via absolute path symlink in TarUtils

Source: https://junglewise.ai/threats/cve-2026-49248-onedev-arbitrary-file-write-via-absolute-path-symlink-in-tarutils  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-18. Updated: 2026-06-21  
License: CC BY 4.0 with a link back

CVE-2026-49248 · Severity: info · CVSS 8.3 · Published 2026-06-18

OneDev, an open-source Git server with CI/CD capabilities, contains a vulnerability that allows users with permission to edit CI/CD jobs to write files to any location on the server. By uploading a specially crafted archive file, an attacker can bypass security restrictions to overwrite critical system files or configuration. This can lead to a complete takeover of the server and potential remote code execution, compromising all hosted code and customer data.

Technologies: [OneDev](https://junglewise.ai/threats/technologies/onedev). Vendors: [OneDev](https://junglewise.ai/threats/vendors/onedev).

## Quick answers

**Is CVE-2026-49248 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-49248 being exploited in the wild.

**How severe is CVE-2026-49248?** Informational severity, with a CVSS score of 8.3, published 18 June 2026.

**Which products and versions are affected?** OneDev <= 15.0.6.

**Is there a fix for CVE-2026-49248?** A patch was published on 2026-05-24: Fixed in version 15.0.7 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-49248 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-49248?** Check whether you run OneDev at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A symlink following vulnerability exists in OneDev's TarUtils.untar() component due to improper validation of TAR archive entries. While a previous fix (CVE-2021-21251) blocked directory traversal using '..' segments, it failed to account for absolute paths in symbolic link targets. An attacker with CI Job write access can craft a TAR archive containing a symlink pointing to an absolute path on the server, followed by a file entry that traverses that symlink. This allows for arbitrary file writes on the server host, which can be leveraged for Remote Code Execution (RCE). The issue is resolved in version 15.0.7.

## Affected products

- theonedev OneDev <= 15.0.6

## Timeline

- 2026-05-24: advisory: GitHub Security Advisory published
- 2026-06-18: disclosed: CVE published to NVD
- 2026-05-24: patched: Fixed in version 15.0.7

## References

- [https://github.com/theonedev/onedev/commit/4f8684acebc4bfeefd3c7e23a34a4fd591cb27ad](https://github.com/theonedev/onedev/commit/4f8684acebc4bfeefd3c7e23a34a4fd591cb27ad)
- [https://github.com/theonedev/onedev/security/advisories/GHSA-55g8-94r5-cj37](https://github.com/theonedev/onedev/security/advisories/GHSA-55g8-94r5-cj37)

## Related threats

- [theonedev OneDev improper authorization in Pull Request Handler](https://junglewise.ai/threats/cve-2026-11441-theonedev-onedev-improper-authorization-in-pull-request-handler)
- [theonedev OneDev improper authorization in REST API default-branch endpoint](https://junglewise.ai/threats/cve-2026-11440-theonedev-onedev-improper-authorization-in-rest-api-default)
- [theonedev OneDev improper authorization in Parent Project Handler](https://junglewise.ai/threats/cve-2026-11439-theonedev-onedev-improper-authorization-in-parent-project-handler)
- [theonedev OneDev improper authorization in project fork functionality](https://junglewise.ai/threats/cve-2026-11438-theonedev-onedev-improper-authorization-in-project-fork)
- [OneDev path traversal in Git LFS pointer resolution](https://junglewise.ai/threats/cve-2026-44647-onedev-path-traversal-in-git-lfs-pointer-resolution)