CVE-2026-5398
Kernel use-after-free bug in the TIOCNOTTY handler
Description
The implementation of TIOCNOTTY failed to clear a back-pointer from the structure representing the controlling terminal to the calling process' session. If the invoking process then exits, the terminal structure may end up containing a pointer to freed memory. A malicious process can abuse the dangling pointer to grant itself root privileges.
INFO
Published Date :
April 22, 2026, 3:16 a.m.
Last Modified :
May 1, 2026, 12:49 p.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
Solution
- Correct the TIOCNOTTY implementation to clear back-pointers.
- Ensure terminal structures do not point to freed memory.
- Remove dangling pointers from terminal structures.
- Validate session management after process exit.
Public PoC/Exploit Available at Github
CVE-2026-5398 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-5398.
| URL | Resource |
|---|---|
| https://security.freebsd.org/advisories/FreeBSD-SA-26:10.tty.asc | Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-5398 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-5398
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Tracking Vulnerabilities That Appear to be Credited to the Anthropic Research Team
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-5398 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-5398 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
May. 01, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:o:freebsd:freebsd:15.0:p1:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:15.0:p2:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:p1:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:p2:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:p3:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:p4:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:p5:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:p6:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:p7:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:p8:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:-:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:p9:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.3:-:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.3:p1:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.3:p2:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.3:p3:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.3:p4:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.3:p5:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.3:p6:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.3:p7:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.3:p8:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:15.0:-:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.4:rc1:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:15.0:p3:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.3:p9:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.4:-:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:15.0:p4:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:beta3:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:p10:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:13.5:p11:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.3:p10:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:14.4:p1:*:*:*:*:*:* *cpe:2.3:o:freebsd:freebsd:15.0:p5:*:*:*:*:*:* Added Reference Type FreeBSD: https://security.freebsd.org/advisories/FreeBSD-SA-26:10.tty.asc Types: Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Apr. 22, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H -
New CVE Received by [email protected]
Apr. 22, 2026
Action Type Old Value New Value Added Description The implementation of TIOCNOTTY failed to clear a back-pointer from the structure representing the controlling terminal to the calling process' session. If the invoking process then exits, the terminal structure may end up containing a pointer to freed memory. A malicious process can abuse the dangling pointer to grant itself root privileges. Added CWE CWE-416 Added Reference https://security.freebsd.org/advisories/FreeBSD-SA-26:10.tty.asc