High severity · published Apr 6, 2026
CVE-2026-31407
netfilter: conntrack: add missing netlink policy validations
7.1
CVSS
0.2%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: add missing netlink policy validations Hyunwoo Kim reports out-of-bounds access in sctp and ctnetlink. These attributes are used by the kernel without any validation. Extend the netlink policies accordingly. Quoting the reporter: nlattr_to_sctp() assigns the user-supplied CTA_PROTOINFO_SCTP_STATE value directly to ct->proto.sctp.state without checking that it is within the valid range. [..] and: ... with exp->dir = 100, the access at ct->master->tuplehash[100] reads 5600 bytes past the start of a 320-byte nf_conn object, causing a slab-out-of-bounds read confirmed by UBSAN.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
2.6.27 before 6.6.136; 6.7 before 6.12.83; 6.13 before 6.18.24; 6.19 before 6.19.10; 7.0; 7.0; +2 more · source: NVD
LI
Linux · Linux
a258860e01b80e8f554a4ab1a6c95e6042eb8b73 before e7b5766693477c52424cc6c79dd30a7a9c7db52c; a258860e01b80e8f554a4ab1a6c95e6042eb8b73 before 78bba9f73942aa7dca47d817d8cec0fb9b443b70; a258860e01b80e8f554a4ab1a6c95e6042eb8b73 before be88a337bf07afb1ee173f1099294d1b7ab3fefe; a258860e01b80e8f554a4ab1a6c95e6042eb8b73 before c5e918390002edf0cff80a0e7ce1f86f16a9507c; a258860e01b80e8f554a4ab1a6c95e6042eb8b73 before 9174d28f3f15d8c4962f5980c0be167633880443; a258860e01b80e8f554a4ab1a6c95e6042eb8b73 before 67c53c1978cef3c504237275e39c857e2f6af56e; +3 more · source: vendor