CVE-2026-72256

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_cluster: reject template conntracks in hash match xt_cluster_mt() treats any non-NULL nf_ct_get() result as a fully initialized conntrack and passes it to xt_cluster_hash(). This causes a state confusion bug when the raw table CT target attaches a template conntrack to skb->_nfct before normal conntrack processing. Templates carry IPS_TEMPLATE status but do not have a valid tuple for hashing yet, so xt_cluster_hash() can hit its WARN_ON() path on the zeroed l3num field. Reject template conntracks before hashing them. This matches existing netfilter handling for template objects and avoids hashing incomplete conntrack state.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/07f9ddbf5e799c24a3a52ec9bd7b729a6f6d69d5
https://git.kernel.org/stable/c/13ea4f86cf738c74be2146886ac261988a631e62
https://git.kernel.org/stable/c/4558bd7b47c7be82dffd837f27be8ea3ecee557d
https://git.kernel.org/stable/c/4cb8b5f586e41c187942291cc0938006077fa79e
https://git.kernel.org/stable/c/5b2d4f0010018a7aa3495aa1dbf1b7a34011e7aa
https://git.kernel.org/stable/c/5feba91006ec92da57acc1cc2e34df623b98541e
https://git.kernel.org/stable/c/d5f9d050b0b267227c1f02f11021872c7768a9cc
https://git.kernel.org/stable/c/fac2fdac3baad9ffd12b3b0bba4374d4b3585d54

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-15 06:21

Updated : 2026-08-17 06:18

NVD link : CVE-2026-72256

Mitre link : CVE-2026-72256

CVE.ORG link : CVE-2026-72256

JSON object : View

Products Affected

No product.

CWE

No CWE.

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