CVE-2026-23247

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux28ee1b746f493b7c62347d714f58fbf4f70df4f0 < 5da5662181ef8a251e3ba564903002c2e87de452affected
LinuxLinux28ee1b746f493b7c62347d714f58fbf4f70df4f0 < eae2f14ab2efccdb7480fae7d42c4b0116ef8805affected
LinuxLinux28ee1b746f493b7c62347d714f58fbf4f70df4f0 < 46e5b0d7cf55821527adea471ffe52a5afbd9cafaffected
LinuxLinux28ee1b746f493b7c62347d714f58fbf4f70df4f0 < 165573e41f2f66ef98940cf65f838b2cb575d9d1affected
LinuxLinux443fac9f2618b93cbc5ab068dc594530236b3a23affected
LinuxLinux4.10.14 < 4.11affected
LinuxLinux4.11affected
LinuxLinux0 < 4.11unaffected
LinuxLinux6.12.94 <= 6.12.*unaffected
LinuxLinux6.18.17 <= 6.18.*unaffected
LinuxLinux6.19.7 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References