{"id":"CVE-2024-35944","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nVMCI: Fix memcpy() run-time warning in dg_dispatch_as_host()\n\nSyzkaller hit 'WARNING in dg_dispatch_as_host' bug.\n\nmemcpy: detected field-spanning write (size 56) of si…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nVMCI: Fix memcpy() run-time warning in dg_dispatch_as_host()\n\nSyzkaller hit 'WARNING in dg_dispatch_as_host' bug.\n\nmemcpy: detected field-spanning write (size 56) of si…","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","vendor":"linux","product":"linux_kernel","affected":["linux_kernel < 4.19.312","linux_kernel >= 4.20, < 5.4.274","linux_kernel >= 5.5, < 5.10.215","linux_kernel >= 5.11, < 5.15.155","linux_kernel >= 5.16, < 6.1.86","linux_kernel >= 6.2, < 6.6.27","linux_kernel >= 6.7, < 6.8.6","debian_linux = 10.0"],"patched":["linux_kernel 6.8.6"],"published":"2024-05-19","updated":"2026-10-15","sourceUpdated":"2026-10-15T01:17:54.707","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2024-35944","references":[{"url":"https://git.kernel.org/stable/c/130b0cd064874e0d0f58e18fb00e6f3993e90c74","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/19b070fefd0d024af3daa7329cbc0d00de5302ec","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/491a1eb07c2bd8841d63cb5263455e185be5866f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ad78c5047dc4076d0b3c4fad4f42ffe9c86e8100","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/dae70a57565686f16089737adb8ac64471570f73","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e87bb99d2df6512d8ee37a5d63d2ca9a39a8c051","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f15eca95138b3d4ec17b63c3c1937b0aa0d3624b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/feacd430b42bbfa9ab3ed9e4f38b86c43e348c75","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/130b0cd064874e0d0f58e18fb00e6f3993e90c74","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/19b070fefd0d024af3daa7329cbc0d00de5302ec","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/491a1eb07c2bd8841d63cb5263455e185be5866f","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/ad78c5047dc4076d0b3c4fad4f42ffe9c86e8100","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/dae70a57565686f16089737adb8ac64471570f73","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/e87bb99d2df6512d8ee37a5d63d2ca9a39a8c051","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/f15eca95138b3d4ec17b63c3c1937b0aa0d3624b","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.kernel.org/stable/c/feacd430b42bbfa9ab3ed9e4f38b86c43e348c75","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-265688.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-398330.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.00234,"epssPercentile":0.14283,"ingestedAt":"2026-10-15T03:30:12.691Z","ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2024-05-20T14:30:02.800597Z"},"slug":"CVE-2024-35944","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nVMCI: Fix memcpy() run-time warning in dg_dispatch_as_host()\n\nSyzkaller hit 'WARNING in dg_dispatch_as_host' bug.\n\nmemcpy: detected field-spanning write (size 56) of single field \"&dg_info->msg\"\nat drivers/misc/vmw_vmci/vmci_datagram.c:237 (size 24)\n\nWARNING: CPU: 0 PID: 1555 at drivers/misc/vmw_vmci/vmci_datagram.c:237\ndg_dispatch_as_host+0x88e/0xa60 drivers/misc/vmw_vmci/vmci_datagram.c:237\n\nSome code commentry, based on my understanding:\n\n544 #define VMCI_DG_SIZE(_dg) (VMCI_DG_HEADERSIZE + (size_t)(_dg)->payload_size)\n/// This is 24 + payload_size\n\nmemcpy(&dg_info->msg, dg, dg_size);\n\tDestination = dg_info->msg ---> this is a 24 byte\n\t\t\t\t\tstructure(struct vmci_datagram)\n\tSource = dg --> this is a 24 byte structure (struct vmci_datagram)\n\tSize = dg_size = 24 + payload_size\n\n{payload_size = 56-24 =32} -- Syzkaller managed to set payload_size to 32.\n\n 35 struct delayed_datagram_info {\n 36         struct datagram_entry *entry;\n 37         struct work_struct work;\n 38         bool in_dg_host_queue;\n 39         /* msg and msg_payload must be together. */\n 40         struct vmci_datagram msg;\n 41         u8 msg_payload[];\n 42 };\n\nSo those extra bytes of payload are copied into msg_payload[], a run time\nwarning is seen while fuzzing with Syzkaller.\n\nOne possible way to fix the warning is to split the memcpy() into\ntwo parts -- one -- direct assignment of msg and second taking care of payload.\n\nGustavo quoted:\n\"Under FORTIFY_SOURCE we should not copy data across multiple members\nin a structure.\"\n\n## Affected\n\n- `linux_kernel < 4.19.312`\n- `linux_kernel >= 4.20, < 5.4.274`\n- `linux_kernel >= 5.5, < 5.10.215`\n- `linux_kernel >= 5.11, < 5.15.155`\n- `linux_kernel >= 5.16, < 6.1.86`\n- `linux_kernel >= 6.2, < 6.6.27`\n- `linux_kernel >= 6.7, < 6.8.6`\n- `debian_linux = 10.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.8.6`","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}