CVE-2026-23247

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: down…

Vendor / product: Linux — linux kernel

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

5.5

5.5 (CVSS v3.1)

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

Severity source: NVD CVSS v3.1 (nvd@nist.gov)

Timeline (UTC)

Published: 2026-03-18 11:16

Modified: 2026-10-30 13:18

NVD status: Modified

Last synced 3 days ago

Verified against the source API 2026-10-30 13:38 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

linux / linux_kernel >4.11 <6.18.17, ≥6.19 <6.19.7, 4.10.14, 4.11, 7.0

Weakness classification (CWE)

NVD-CWE-noinfo

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Patch / mitigation: https://git.kernel.org/stable/c/165573e41f2f66ef98940cf65f838b2cb575d9d1

Patch / mitigation: https://git.kernel.org/stable/c/46e5b0d7cf55821527adea471ffe52a5afbd9caf

Patch / mitigation: https://git.kernel.org/stable/c/eae2f14ab2efccdb7480fae7d42c4b0116ef8805

References

https://git.kernel.org/stable/c/025f532d8c5cfac77845e50daab7f478b360f2ac 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/165573e41f2f66ef98940cf65f838b2cb575d9d1 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/46e5b0d7cf55821527adea471ffe52a5afbd9caf 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/5da5662181ef8a251e3ba564903002c2e87de452 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/e873e8c16b2fb743a381a9e59c108e63512301ec 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/eae2f14ab2efccdb7480fae7d42c4b0116ef8805 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Data sources

NVD CVE API 2.0 — fetched 2026-10-30 13:38 UTC · record ↗

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CVE-2026-23247

Affected products

Weakness classification (CWE)

Mitigation & advisories

References

Data sources

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