CVE-2026-72256netfilter: xt_cluster: reject template conntracks in hash match
Updated under an hour ago ()
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No exploitation reported and no EPSS estimate yet.
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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
- Not yet scored
- Weakness (CWE)
- Not given
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Linux
- NVD analysis
- Received
- Record last updated
- Aug 17, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Linux Linux linux:linux (from the name) | from 0269ea4937343536ec7e85649932bc8c9686ea78 before 4558bd7b47c7be82dffd837f27be8ea3ecee557d; from 0269ea4937343536ec7e85649932bc8c9686ea78 before d5f9d050b0b267227c1f02f11021872c7768a9cc; 0269ea4937343536ec7e85649932bc8c9686ea78 builds before 4cb8b5f586e41c187942291cc0938006077fa79e; from 0269ea4937343536ec7e85649932bc8c9686ea78 before fac2fdac3baad9ffd12b3b0bba4374d4b3585d54; 0269ea4937343536ec7e85649932bc8c9686ea78 builds before 13ea4f86cf738c74be2146886ac261988a631e62; 0269ea4937343536ec7e85649932bc8c9686ea78 builds before 07f9ddbf5e799c24a3a52ec9bd7b729a6f6d69d5; 0269ea4937343536ec7e85649932bc8c9686ea78 builds before 5b2d4f0010018a7aa3495aa1dbf1b7a34011e7aa; 0269ea4937343536ec7e85649932bc8c9686ea78 builds before 5feba91006ec92da57acc1cc2e34df623b98541e | CNA record |
References
- https://git.kernel.org/stable/c/4558bd7b47c7be82dffd837f27be8ea3ecee557d
- https://git.kernel.org/stable/c/d5f9d050b0b267227c1f02f11021872c7768a9cc
- https://git.kernel.org/stable/c/4cb8b5f586e41c187942291cc0938006077fa79e
- https://git.kernel.org/stable/c/fac2fdac3baad9ffd12b3b0bba4374d4b3585d54
- https://git.kernel.org/stable/c/13ea4f86cf738c74be2146886ac261988a631e62
- https://git.kernel.org/stable/c/07f9ddbf5e799c24a3a52ec9bd7b729a6f6d69d5
- https://git.kernel.org/stable/c/5b2d4f0010018a7aa3495aa1dbf1b7a34011e7aa
- https://git.kernel.org/stable/c/5feba91006ec92da57acc1cc2e34df623b98541e
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.