Buffer overflow in FreeBSD
CVE-2026-101307
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- security.freebsd.org/advisories/FreeBSD-SA-26:70.tcp.asc (vendor-advisory)
Frequently asked questions
- What is CVE-2026-101307?
- CVE-2026-101307 is a medium-severity vulnerability in FreeBSD, classified under Heap-based Buffer Overflow. CVSS score: 6.5/10. Published 2026-10-15.
- How severe is CVE-2026-101307?
- Medium severity. CVSS v3 base score is 6.5 out of 10.