Vulnerability in Linux

CVE-2026-89476

In the Linux kernel, the following vulnerability has been resolved: sctp: fix stream->outcnt underflow on duplicate RECONF responses A cached RECONF chunk may contain more than one request parameter. A duplicate response can therefore find and process the same ADD_OUT request again while another parameter is still outstanding, rolling back outcnt twice and possibly underflowing it. Track outstanding request types as bits and clear each bit after its first response. Later responses for the same request are then ignored.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.007 (52.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 53rd percentile — 52.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-89476: held from 0.007 to 0.007.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: -0.000

Affected products

References

Frequently asked questions

What is CVE-2026-89476?
CVE-2026-89476 is a high-severity vulnerability in Linux. CVSS score: 7.5/10. Published 2026-09-11.
How severe is CVE-2026-89476?
High severity. CVSS v3 base score is 7.5 out of 10.