In the Linux kernel, the following vulnerability has been resolved:

net: mctp: Don't access ifa_index when missing

In mctp_dump_addrinfo, ifa_index can be used to filter interfaces, but
only when the struct ifaddrmsg is provided. Otherwise it will be
comparing to uninitialised memory - reproducible in the syzkaller case from
dhcpd, or busybox "ip addr show".

The kernel MCTP implementation has always filtered by ifa_index, so
existing userspace programs expecting to dump MCTP addresses must
already be passing a valid ifa_index value (either 0 or a real index).

BUG: KMSAN: uninit-value in mctp_dump_addrinfo+0x208/0xac0 net/mctp/device.c:128
mctp_dump_addrinfo+0x208/0xac0 net/mctp/device.c:128
rtnl_dump_all+0x3ec/0x5b0 net/core/rtnetlink.c:4380
rtnl_dumpit+0xd5/0x2f0 net/core/rtnetlink.c:6824
netlink_dump+0x97b/0x1690 net/netlink/af_netlink.c:2309
Advisories
Source ID Title
EUVD EUVD EUVD-2025-27859 In the Linux kernel, the following vulnerability has been resolved: net: mctp: Don't access ifa_index when missing In mctp_dump_addrinfo, ifa_index can be used to filter interfaces, but only when the struct ifaddrmsg is provided. Otherwise it will be comparing to uninitialised memory - reproducible in the syzkaller case from dhcpd, or busybox "ip addr show". The kernel MCTP implementation has always filtered by ifa_index, so existing userspace programs expecting to dump MCTP addresses must already be passing a valid ifa_index value (either 0 or a real index). BUG: KMSAN: uninit-value in mctp_dump_addrinfo+0x208/0xac0 net/mctp/device.c:128 mctp_dump_addrinfo+0x208/0xac0 net/mctp/device.c:128 rtnl_dump_all+0x3ec/0x5b0 net/core/rtnetlink.c:4380 rtnl_dumpit+0xd5/0x2f0 net/core/rtnetlink.c:6824 netlink_dump+0x97b/0x1690 net/netlink/af_netlink.c:2309
Ubuntu USN Ubuntu USN USN-7699-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7699-2 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7721-1 Linux kernel (Azure) vulnerabilities
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 14 Nov 2025 16:45:00 +0000

Type Values Removed Values Added
Weaknesses CWE-908
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.15:rc6:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}


Sat, 21 Jun 2025 12:45:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Moderate


Wed, 18 Jun 2025 09:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: net: mctp: Don't access ifa_index when missing In mctp_dump_addrinfo, ifa_index can be used to filter interfaces, but only when the struct ifaddrmsg is provided. Otherwise it will be comparing to uninitialised memory - reproducible in the syzkaller case from dhcpd, or busybox "ip addr show". The kernel MCTP implementation has always filtered by ifa_index, so existing userspace programs expecting to dump MCTP addresses must already be passing a valid ifa_index value (either 0 or a real index). BUG: KMSAN: uninit-value in mctp_dump_addrinfo+0x208/0xac0 net/mctp/device.c:128 mctp_dump_addrinfo+0x208/0xac0 net/mctp/device.c:128 rtnl_dump_all+0x3ec/0x5b0 net/core/rtnetlink.c:4380 rtnl_dumpit+0xd5/0x2f0 net/core/rtnetlink.c:6824 netlink_dump+0x97b/0x1690 net/netlink/af_netlink.c:2309
Title net: mctp: Don't access ifa_index when missing
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-06-18T09:28:17.773Z

Reserved: 2025-04-16T04:51:23.977Z

Link: CVE-2025-38006

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2025-06-18T10:15:31.773

Modified: 2025-11-14T16:42:01.430

Link: CVE-2025-38006

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-06-18T00:00:00Z

Links: CVE-2025-38006 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-06-23T08:53:47Z