CVE-2026-45840

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

27/05/2026

Last modified:

26/06/2026

Description

In the Linux kernel, the following vulnerability has been resolved: openvswitch: cap upcall PID array size and pre-size vport replies The vport netlink reply helpers allocate a fixed-size skb with nlmsg_new(NLMSG_DEFAULT_SIZE, ...) but serialize the full upcall PID array via ovs_vport_get_upcall_portids(). Since ovs_vport_set_upcall_portids() accepts any non-zero multiple of sizeof(u32) with no upper bound, a CAP_NET_ADMIN user can install a PID array large enough to overflow the reply buffer, causing nla_put() to fail with -EMSGSIZE and hitting BUG_ON(err

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 5.50 MEDIUM
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): None
Availability (A): High

Base Score 3.x

5.50

Severity 3.x

MEDIUM

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:o:linux:linux_kernel::::::::	3.17 (including)	5.10.258 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	5.11 (including)	5.15.209 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	5.16 (including)	6.1.175 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.2 (including)	6.6.141 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.7 (including)	6.12.91 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.13 (including)	6.18.33 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.19 (including)	7.0.10 (excluding)

To consult the complete list of CPE names with products and versions, see this page

CVE-2026-45840

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools