CVE-2026-23247

MEDIUM

tcp: secure_seq: add back ports to TS offset

Title source: cna
STIX 2.1

Description

In the Linux kernel, the following vulnerability has been resolved: tcp: secure_seq: add back ports to TS offset This reverts 28ee1b746f49 ("secure_seq: downgrade to per-host timestamp offsets") tcp_tw_recycle went away in 2017. Zhouyan Deng reported off-path TCP source port leakage via SYN cookie side-channel that can be fixed in multiple ways. One of them is to bring back TCP ports in TS offset randomization. As a bonus, we perform a single siphash() computation to provide both an ISN and a TS offset.

Scores

CVSS v3 5.5
EPSS 0.0012
EPSS Percentile 2.0%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Details

Status published
Products (21)
linux/Kernel 4.11.0 - 6.12.94linux
linux/Kernel 4.11.0 - 6.18.17linux
linux/Kernel 6.13.0 - 6.18.17linux
linux/Kernel 6.19.0 - 6.19.7linux
Linux/Linux < 4.11
Linux/Linux 28ee1b746f493b7c62347d714f58fbf4f70df4f0 - 165573e41f2f66ef98940cf65f838b2cb575d9d1
Linux/Linux 28ee1b746f493b7c62347d714f58fbf4f70df4f0 - 46e5b0d7cf55821527adea471ffe52a5afbd9caf
Linux/Linux 28ee1b746f493b7c62347d714f58fbf4f70df4f0 - 5da5662181ef8a251e3ba564903002c2e87de452
Linux/Linux 28ee1b746f493b7c62347d714f58fbf4f70df4f0 - eae2f14ab2efccdb7480fae7d42c4b0116ef8805
Linux/Linux 4.10.14 - 4.11
... and 11 more
Published Mar 18, 2026
Tracked Since Mar 18, 2026