Copyright © 2012 Red Hat, Inc. All rights reserved. Moderate 2026-08-26T00:00:00 kernel: mptcp: reclaim forward-allocated memory on RX path errors 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CWE-772

In the Linux kernel, the following vulnerability has been resolved: mptcp: reclaim forward-allocated memory on RX path errors After commit 9db5b3cec4ec ("mptcp: borrow forward memory from subflow"), errors in the receive path prior to queueing skbs into the receive queue do not trigger forward-allocated memory reclaiming. Prevent forward memory from growing unboundedly in pathological drop scenarios by explicitly reclaiming memory when skbs are dropped.

A flaw was found in the Linux kernel's Multipath TCP (mptcp) implementation. Errors occurring during the receive path, before data is queued, may prevent the system from reclaiming forward-allocated memory. This can lead to an unbounded increase in memory usage under certain network conditions, such as high packet loss. A remote attacker could exploit this vulnerability to cause a Denial of Service (DoS) by exhausting available system memory.

Red Hat Enterprise Linux 10 Fix deferred kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Fix deferred kernel Red Hat Enterprise Linux 9 Fix deferred kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-80588 https://nvd.nist.gov/vuln/detail/CVE-2026-80588 https://lore.kernel.org/linux-cve-announce/2026082616-CVE-2026-80588-cd6f@gregkh/T