cbcvebase.
CVE-2025-40043
published 2025-10-28

CVE-2025-40043: In the Linux kernel, the following vulnerability has been resolved: net: nfc: nci: Add parameter validation for packet data Syzbot reported an uninitialized…

PriorityP347high8.8CVSS 3.1
AVAACLPRNUINSUCHIHAH
EPSS
0.29%
21.6th percentile
In the Linux kernel, the following vulnerability has been resolved: net: nfc: nci: Add parameter validation for packet data Syzbot reported an uninitialized value bug in nci_init_req, which was introduced by commit 5aca7966d2a7 ("Merge tag 'perf-tools-fixes-for-v6.17-2025-09-16' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools"). This bug arises due to very limited and poor input validation that was done at nic_valid_size(). This validation only validates the skb->len (directly reflects size provided at the userspace interface) with the length provided in the buffer itself (interpreted as NCI_HEADER). This leads to the processing of memory content at the address assuming the correct layout per what opcode requires there. This leads to the accesses to buffer of `skb_buff->data` which is not assigned anything yet. Following the same silent drop of packets of invalid sizes at `nic_valid_size()`, add validation of the data in the respective handlers and return error values in case of failure. Release the skb if error values are returned from handlers in `nci_nft_packet` and effectively do a silent drop Possible TODO: because we silently drop the packets, the call to `nci_request` will be waiting for completion of request and will face timeouts. These timeouts can get excessively logged in the dmesg. A proper handling of them may require to export `nci_request_cancel` (or propagate error handling from the nft packets handlers).

Affected

27 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.158-1 (bookworm)linux 6.1.158-1 (bookworm)
debianlinux-6.1< linux 6.1.158-1 (bookworm)linux 6.1.158-1 (bookworm)
linuxlinux
linuxlinux>= 6a2968aaf50c7a22fced77a5e24aa636281efca8 < 8fcc7315a10a84264e55bb65ede10f0af20a983f8fcc7315a10a84264e55bb65ede10f0af20a983f
linuxlinux>= 6a2968aaf50c7a22fced77a5e24aa636281efca8 < bfdda0123dde406dbff62e7e9136037e97998a15bfdda0123dde406dbff62e7e9136037e97998a15
linuxlinux>= 6a2968aaf50c7a22fced77a5e24aa636281efca8 < 0ba68bea1e356f466ad29449938bea12f5f3711f0ba68bea1e356f466ad29449938bea12f5f3711f
linuxlinux>= 6a2968aaf50c7a22fced77a5e24aa636281efca8 < 74837bca0748763a77f77db47a0bdbe63b34762874837bca0748763a77f77db47a0bdbe63b347628
linuxlinux>= 6a2968aaf50c7a22fced77a5e24aa636281efca8 < c395d1e548cc68e84584ffa2e3ca9796a78bf7b9c395d1e548cc68e84584ffa2e3ca9796a78bf7b9
linuxlinux>= 6a2968aaf50c7a22fced77a5e24aa636281efca8 < 9c328f54741bd5465ca1dc717c84c04242fac2e19c328f54741bd5465ca1dc717c84c04242fac2e1
linuxlinux_kernel>= 0 < 6.1.158-16.1.158-1
linuxlinux_kernel>= 0 < 6.12.57-16.12.57-1
linuxlinux_kernel>= 0 < 6.17.6-16.17.6-1
linuxlinux_kernel>= 0 < 5.15.0-170.1805.15.0-170.180
linuxlinux_kernel>= 0 < 6.8.0-106.1066.8.0-106.106
linuxlinux_kernel>= 0 < 6.17.0-14.146.17.0-14.14
linuxlinux_kernel>= 3.2.0 < 5.15.1955.15.195
linuxlinux_kernel>= 5.16.0 < 6.1.1566.1.156
linuxlinux_kernel>= 6.13.0 < 6.17.36.17.3
linuxlinux_kernel>= 6.2.0 < 6.6.1126.6.112
linuxlinux_kernel>= 6.7.0 < 6.12.536.12.53
msrcazl3_kernel_6.6.104.2-4_on_azure_linux_3.0
ubuntulinux-aws
ubuntulinux-azure-5.15
ubuntulinux-intel-iotg-5.15
ubuntulinux-oracle

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_ubuntu7.8HIGH
vendor_msrc6.3MEDIUM
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