# Calif details OpenBSD exploit that bypassed kernel protections to gain root

_Published Friday, October 16, 2026 at 1:08 PM EDT · Security · Latest · Tier 2 — Notable_

Calif published an OpenBSD exploit that it says gained local root access with three kernel protections enabled, without an information disclosure vulnerability. The attack combined an overflow in a shared memory counter inherited from roughly 37-year-old BSD code with a separate kernel write flaw.

Repeated process creation overflowed the counter, enabling a race that let the exploit access freed memory. Predictable kernel allocations then helped it overwrite a function pointer and execute kernel code. Calif says OpenBSD addressed the vulnerabilities in errata 026 and 018. The exploit required local access; it did not establish a remote entry point.

## Sources

- [calif.io](https://calif.io/research/big-fish)

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Canonical: https://techandbusiness.org/newswire/EcLxnrPULrBYNGN8OUQ1bP
Published: 2026-10-16T17:08:35.580Z
Story chronology: 2026-10-16T14:44:02.000Z
Retrieved: 2026-10-16T19:50:17.121Z
Publisher: Tech & Business (techandbusiness.org)