High 7.3Published Aug 15, 2026

CVE-2026-72347netfilter: xt_connmark: reject invalid shift parameters

Updated under an hour ago (Oct 28, 2026, 4:50 AM ET)

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_connmark: reject invalid shift parameters Revision 2 of the CONNMARK target accepts user-controlled shift parameters and applies them to 32-bit mark values in connmark_tg_shift(). A shift_bits value of 32 or more triggers an undefined-shift bug when the rule is evaluated. Invalid shift_dir values are also accepted and silently fall back to the left-shift path. Reject invalid revision-2 shift parameters in connmark_tg_check() so malformed rules fail at installation time, before they can reach the packet path.

CVSS: 7.3 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H
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: Oct 16, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from 472a73e00757b971d613d796374d2727b2e4954d before d8ce63d928b457fba7ed1e302492dfd32293671c; from 472a73e00757b971d613d796374d2727b2e4954d before 9657bb11a6376ab0a79f05d433713d6944111e9d; 472a73e00757b971d613d796374d2727b2e4954d builds before 8ace320ac4416f5e5fbcd065309fb2dfcce787b0; from 472a73e00757b971d613d796374d2727b2e4954d before c3fa852d117b3fda72265e4230e3967db4a74fcf; 472a73e00757b971d613d796374d2727b2e4954d builds before 4eef84b09a3836919360c4232b0f16651a155eec; from 472a73e00757b971d613d796374d2727b2e4954d before 230173cc6105bdfb2696d37e6e56687b003fbe63; 472a73e00757b971d613d796374d2727b2e4954d builds before 1b47026fb4b35bac850ad6e8a4ad7fc018e09ebc	CNA record

References

References

https://git.kernel.org/stable/c/d8ce63d928b457fba7ed1e302492dfd32293671c
https://git.kernel.org/stable/c/9657bb11a6376ab0a79f05d433713d6944111e9d
https://git.kernel.org/stable/c/8ace320ac4416f5e5fbcd065309fb2dfcce787b0
https://git.kernel.org/stable/c/c3fa852d117b3fda72265e4230e3967db4a74fcf
https://git.kernel.org/stable/c/4eef84b09a3836919360c4232b0f16651a155eec
https://git.kernel.org/stable/c/230173cc6105bdfb2696d37e6e56687b003fbe63
https://git.kernel.org/stable/c/1b47026fb4b35bac850ad6e8a4ad7fc018e09ebc

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.