CVE-2026-101307 Remotely triggerable buffer overflow in tcp_rack
A remote attacker can trigger a kernel panic in FreeBSD by causing an integer overflow in the TCP RACK stack, leading to a buffer overflow.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-101307?
CVE-2026-101307 is a high-severity vulnerability in Freebsd Freebsd, published on 15 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
When the PCM sample array needs to grow, the RACK stack doubles a 16-bit allocation counter. Repeated doublings caused the counter to wrap to zero, resulting in a near-zero-length allocation followed by a copy of the existing samples into the undersized buffer. A remote peer can trigger the expansion by sending a sufficient number of ACKs on an established connection.
A remote attacker who can establish a TCP connection to a system using the RACK stack can trigger an out-of-bounds write of approximately 512 KB in the kernel heap possibly resulting in a kernel panic.
Which versions are affected by CVE-2026-101307?
It affects 1 product.
Products include Freebsd Freebsd.
How do I fix CVE-2026-101307?
No fix has been published for CVE-2026-101307 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-101307 being exploited?
There is no known exploitation of CVE-2026-101307 in the wild and no public exploit code.
Other vulnerabilities in Freebsd Freebsd
Sources
Also known as GHSA-gpr4-gr7v-w9p3.