CVE-2026-98547
kernel: af_packet: fix integer overflow in prb_calc_retire_blk_tmo()
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · October 18, 2026
Updated · October 30, 2026
Description
A flaw was found in the Linux kernel's af_packet network socket implementation. An integer overflow occurs during timeout calculations when configuring packet receive rings with large block sizes. A local user with raw network privileges can exploit this vulnerability by setting an oversized socket buffer size, triggering a continuous, high-frequency timer loop. This condition locks CPU resources and can freeze the system, resulting in a Denial of Service (DoS).
Statement
This vulnerability is assessed as Moderate because exploitation requires local raw networking privileges (such as CAP_NET_RAW) and does not permit code execution or data confidentiality compromises. In typical Red Hat Enterprise Linux deployments, unprivileged users cannot open packet sockets unless granted specialized capabilities or operating within custom user namespaces. While an attacker with the necessary privileges can trigger an infinite timer loop by requesting malformed buffer ring parameters to exhaust CPU capacity, the defect does not allow privilege escalation or data tampering.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-190 · Integer Overflow or Wraparound