CVE-2018-7191 — In the tun subsystem in the Linux kernel before 4

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. Th

01What is this vulnerability?

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.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

08Timeline

• Published: 2019-05-17T04:27:00.000Z
• Last modified: 2024-08-05T06:24:10.508Z

09References

• bugs.launchpad.net — https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1743792
• bugs.launchpad.net — https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1748846
• github.com — https://github.com/torvalds/linux/commit/0ad646c81b2182f7fa67ec0c8c825e0ee165696…
• git.kernel.org — https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=0ad64…
• github.com — https://github.com/torvalds/linux/commit/5c25f65fd1e42685f7ccd80e0621829c105785d…
• git.kernel.org — https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5c25f…
• cdn.kernel.org — https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.13.14
• www.securityfocus.com — http://www.securityfocus.com/bid/108380
• lists.opensuse.org — http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00071.html
• lists.opensuse.org — http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00039.html
• lists.opensuse.org — http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00048.html