CVE-2026-5398 (GCVE-0-2026-5398)

Vulnerability from cvelistv5 – Published: 2026-04-22 02:23 – Updated: 2026-04-23 03:56
VLAI?
Title
Kernel use-after-free bug in the TIOCNOTTY handler
Summary
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.
Severity ?
8.4 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version
FreeBSD FreeBSD Affected: 15.0-RELEASE , < p6 (release)
Affected: 14.4-RELEASE , < p2 (release)
Affected: 14.3-RELEASE , < p11 (release)
Affected: 13.5-RELEASE , < p12 (release)
Create a notification for this product.
Date Public ?
2026-04-21 18:00
Credits
Nicholas Carlini using Claude, Anthropic
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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