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CVE-2026-49419 Detail

Description

When the JAIL_AT_DESC flag is specified, kern_jail_set() and kern_jail_get() released the reference to the caller's current prison before looking up the jail descriptor. If the descriptor lookup failed, error-handling paths released the same reference a second time. An unprivileged local user can trigger a prison reference count underflow, which may cause the prison structure to be freed while still in use. When this is done on the jail host, the bug will generally result in an immediate panic. However, if the user is running in a jail, then it may be possible to exploit the bug to elevate privileges.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

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URL Source(s) Tag(s)
FreeBSD

Weakness Enumeration

CWE-ID CWE Name Source
CWE-911 Improper Update of Reference Count FreeBSD  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-49419
NVD Published Date:
08/19/2026
NVD Last Modified:
08/19/2026
Source:
FreeBSD