cbcvebase.
CVE-2025-21972
published 2025-04-01

CVE-2025-21972: In the Linux kernel, the following vulnerability has been resolved: net: mctp: unshare packets when reassembling Ensure that the frag_list used for reassembly…

PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.22%
12.5th percentile
In the Linux kernel, the following vulnerability has been resolved: net: mctp: unshare packets when reassembling Ensure that the frag_list used for reassembly isn't shared with other packets. This avoids incorrect reassembly when packets are cloned, and prevents a memory leak due to circular references between fragments and their skb_shared_info. The upcoming MCTP-over-USB driver uses skb_clone which can trigger the problem - other MCTP drivers don't share SKBs. A kunit test is added to reproduce the issue.

Affected

20 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.12.20-1 (forky)linux 6.12.20-1 (forky)
linuxlinux
linuxlinux>= 4a992bbd365094730a31bae1e12a6ca695336d57 < 5c47d5bfa7b096cf8890afac32141c578583f8e05c47d5bfa7b096cf8890afac32141c578583f8e0
linuxlinux>= 4a992bbd365094730a31bae1e12a6ca695336d57 < f44fff3d3c6cd67b6f348b821d73c4d6888c7a6ef44fff3d3c6cd67b6f348b821d73c4d6888c7a6e
linuxlinux>= 4a992bbd365094730a31bae1e12a6ca695336d57 < f5d83cf0eeb90fade4d5c4d17d24b8bee9ceeeccf5d83cf0eeb90fade4d5c4d17d24b8bee9ceeecc
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.12.20-16.12.20-1
linuxlinux_kernel>= 0 < 6.12.20-16.12.20-1
linuxlinux_kernel>= 0 < 6.8.0-84.846.8.0-84.84
linuxlinux_kernel>= 5.15 < 6.12.206.12.20
linuxlinux_kernel>= 6.13 < 6.13.86.13.8
msrcazl3_kernel_6.6.104.2-4_on_azure_linux_3.0
msrcazl3_kernel_6.6.96.2-1_on_azure_linux_3.0
msrcazl3_kernel_6.6.96.2-2_on_azure_linux_3.0
msrccbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.9MEDIUM
vendor_ubuntu5.9MEDIUM
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
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