CVE-2026-49422 (GCVE-0-2026-49422)
Vulnerability from cvelistv5
Published
2026-08-19 05:28
Modified
2026-08-20 03:55
CWE
Summary
The RACK setsockopt(2) handler drops the connection lock in order to copy option data from userspace, then reacquires the lock. After reacquiring, it verifies that the TCP stack had not been switched away, but did not reload its pointer to the stack's per-connection control block. If userspace switches stacks twice during this window, the check will succeed but the saved pointer will refer to freed memory. The bug may be exploitable by an unprivileged local user to escalate privileges.
Impacted products
Vendor Product Version
FreeBSD FreeBSD Version: 15.1-RELEASE
Version: 15.0-RELEASE
Version: 14.4-RELEASE
Version: 14.3-RELEASE
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Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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