CVE-2026-89476
Published Sep 11, 2026
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.
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References
Other References
Frequently Asked Questions
What is 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.
How do I check if I'm vulnerable to CVE-2026-89476? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.