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Vulnerability record · CVE-2026-89476 · published 11 September 2026

CVE-2026-89476: In the Linux kernel, the following vulnerability has been resolved: sctp: fix stream->outcnt underflow on dup…

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.

7.5 CVSS 3.1 High EPSS 0.72% · top 48.1% Received
7.5CVSS 3.1 base score
0.72%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
8References
14 Sep 2026Last modified by NVD

Description

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.

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

References

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Source: NIST National Vulnerability Database (record CVE-2026-89476), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.