CVE-2026-23247 — MEDIUM (5.5)

Q: How severe is CVE-2026-23247?

CVE-2026-23247 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.

Q: Is there a patch for CVE-2026-23247?

Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.

Vulnerability 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.

CVSS Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

NONE

Availability

HIGH

Affected Products

Vendor	Product	Versions
Linux	Linux Kernel	< 6.18.17

References

FAQ

What is CVE-2026-23247?

CVE-2026-23247 is a vulnerability with a CVSS score of 5.5 (MEDIUM). 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") tc...

How severe is CVE-2026-23247?

CVE-2026-23247 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-23247?

Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.