{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-39987","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-04-16T07:20:57.150Z","datePublished":"2025-10-15T07:56:05.878Z","dateUpdated":"2026-08-05T12:06:54.724Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:06:54.724Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: hi311x: populate ndo_change_mtu() to prevent buffer overflow\n\nSending an PF_PACKET allows to bypass the CAN framework logic and to\ndirectly reach the xmit() function of a CAN driver. The only check\nwhich is performed by the PF_PACKET framework is to make sure that\nskb->len fits the interface's MTU.\n\nUnfortunately, because the sun4i_can driver does not populate its\nnet_device_ops->ndo_change_mtu(), it is possible for an attacker to\nconfigure an invalid MTU by doing, for example:\n\n  $ ip link set can0 mtu 9999\n\nAfter doing so, the attacker could open a PF_PACKET socket using the\nETH_P_CANXL protocol:\n\n\tsocket(PF_PACKET, SOCK_RAW, htons(ETH_P_CANXL))\n\nto inject a malicious CAN XL frames. For example:\n\n\tstruct canxl_frame frame = {\n\t\t.flags = 0xff,\n\t\t.len = 2048,\n\t};\n\nThe CAN drivers' xmit() function are calling can_dev_dropped_skb() to\ncheck that the skb is valid, unfortunately under above conditions, the\nmalicious packet is able to go through can_dev_dropped_skb() checks:\n\n  1. the skb->protocol is set to ETH_P_CANXL which is valid (the\n     function does not check the actual device capabilities).\n\n  2. the length is a valid CAN XL length.\n\nAnd so, hi3110_hard_start_xmit() receives a CAN XL frame which it is\nnot able to correctly handle and will thus misinterpret it as a CAN\nframe. The driver will consume frame->len as-is with no further\nchecks.\n\nThis can result in a buffer overflow later on in hi3110_hw_tx() on\nthis line:\n\n\tmemcpy(buf + HI3110_FIFO_EXT_DATA_OFF,\n\t       frame->data, frame->len);\n\nHere, frame->len corresponds to the flags field of the CAN XL frame.\nIn our previous example, we set canxl_frame->flags to 0xff. Because\nthe maximum expected length is 8, a buffer overflow of 247 bytes\noccurs!\n\nPopulate net_device_ops->ndo_change_mtu() to ensure that the\ninterface's MTU can not be set to anything bigger than CAN_MTU. By\nfixing the root cause, this prevents the buffer overflow."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - Exploitation requires local syscalls — creating a PF_PACKET raw socket and sendmsg() to the CAN interface (optionally an rtnetlink MTU change) — on the machine hosting the SPI-attached HI-3110 controller. No remote or adjacent-network path reaches this xmit function.\nAC:L - The overflow is fully deterministic: a single crafted CAN XL frame with flags=0xFF makes frame->len=255 unconditionally, with no race, no timing window, and no dependence on memory layout to trigger.\nPR:L - The attacker needs only CAP_NET_RAW to open the PF_PACKET socket (and CAP_NET_ADMIN for the larger fully-controlled payload variant), both of which are held by unprivileged principals inside user/network namespaces and by containerized automotive and industrial CAN applications that own the delegated can0 interface.\nUI:N - The attacker sends the malicious frame entirely on their own; no victim action, mount, or file open is involved.\nS:U - The corruption occurs in kernel stack and slab memory within the same kernel security authority as the attacking process; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - hi3110_spi_trans() transmits 262 bytes out of a 15-byte devm_kzalloc'd buffer, shifting ~247 bytes of adjacent kernel heap memory onto the externally observable SPI/CAN bus, and the memcpy also over-reads the skb; the stack/heap corruption further yields disclosure primitives.\nI:H - Up to 247 bytes of attacker-controlled data are written past a 14-byte kernel stack buffer, overwriting the canary, saved registers and return address, plus a matching slab overflow — a classic control-flow hijack and arbitrary-write primitive enabling privilege escalation.\nA:H - The stack smash trips the stack protector (panic) or corrupts the workqueue thread's frame, and the concurrent slab overflow corrupts neighbouring heap objects, reliably producing a kernel oops or panic."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/can/spi/hi311x.c"],"versions":[{"version":"57e83fb9b7468c75cb65cde1d23043553c346c6d","lessThan":"f2c247e9581024d8b3dd44cbe086bf2bebbef42c","status":"affected","versionType":"git"},{"version":"57e83fb9b7468c75cb65cde1d23043553c346c6d","lessThan":"8f351db6b2367991f0736b2cff082f5de4872113","status":"affected","versionType":"git"},{"version":"57e83fb9b7468c75cb65cde1d23043553c346c6d","lessThan":"7ab85762274c0fa997f0ef9a2307b2001aae43c4","status":"affected","versionType":"git"},{"version":"57e83fb9b7468c75cb65cde1d23043553c346c6d","lessThan":"57d332ce8c921d0e340650470bb0c1d707f216ee","status":"affected","versionType":"git"},{"version":"57e83fb9b7468c75cb65cde1d23043553c346c6d","lessThan":"be1b25005fd0f9d4e78bec6695711ef87ee33398","status":"affected","versionType":"git"},{"version":"57e83fb9b7468c75cb65cde1d23043553c346c6d","lessThan":"def814b4ba31b563584061d6895d5ff447d5bc14","status":"affected","versionType":"git"},{"version":"57e83fb9b7468c75cb65cde1d23043553c346c6d","lessThan":"e77fdf9e33a83a08f04ab0cb68c19ddb365a622f","status":"affected","versionType":"git"},{"version":"57e83fb9b7468c75cb65cde1d23043553c346c6d","lessThan":"ac1c7656fa717f29fac3ea073af63f0b9919ec9a","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/can/spi/hi311x.c"],"versions":[{"version":"4.12","status":"affected"},{"version":"0","lessThan":"4.12","status":"unaffected","versionType":"semver"},{"version":"5.4.300","lessThanOrEqual":"5.4.*","status":"unaffected","versionType":"semver"},{"version":"5.10.245","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.194","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.155","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.109","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.50","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.16.10","lessThanOrEqual":"6.16.*","status":"unaffected","versionType":"semver"},{"version":"6.17","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"5.4.300"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"5.10.245"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"5.15.194"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.1.155"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.6.109"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.12.50"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.16.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.17"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/f2c247e9581024d8b3dd44cbe086bf2bebbef42c"},{"url":"https://git.kernel.org/stable/c/8f351db6b2367991f0736b2cff082f5de4872113"},{"url":"https://git.kernel.org/stable/c/7ab85762274c0fa997f0ef9a2307b2001aae43c4"},{"url":"https://git.kernel.org/stable/c/57d332ce8c921d0e340650470bb0c1d707f216ee"},{"url":"https://git.kernel.org/stable/c/be1b25005fd0f9d4e78bec6695711ef87ee33398"},{"url":"https://git.kernel.org/stable/c/def814b4ba31b563584061d6895d5ff447d5bc14"},{"url":"https://git.kernel.org/stable/c/e77fdf9e33a83a08f04ab0cb68c19ddb365a622f"},{"url":"https://git.kernel.org/stable/c/ac1c7656fa717f29fac3ea073af63f0b9919ec9a"}],"title":"can: hi311x: populate ndo_change_mtu() to prevent buffer overflow","x_generator":{"engine":"bippy-1.2.0"}}}}