{"id":"CVE-2026-64188","state":"PUBLISHED","title":"net: qualcomm: rmnet: fix endpoint use-after-free in rmnet_dellink()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: qualcomm: rmnet: fix endpoint use-after-free in rmnet_dellink()\n\nrmnet_dellink() removes the endpoint from the hash table with\nhlist_del_init_rcu() and then immediately frees it with kfree(). However,\nRCU readers on the receive path (rmnet_rx_handler ->\n__rmnet_map_ingress_handler) may still hold a reference to the endpoint and\ndereference ep->egress_dev after the memory has been freed. The endpoint is\na kmalloc-32 object, and the stale read at offset 8 corresponds to the\negress_dev pointer.\n\n  BUG: unable to handle page fault for address: ffffffffde942eef\n  Oops: 0002 [#1] SMP NOPTI\n  CPU: 1 UID: 0 PID: 137 Comm: poc_write Not tainted 7.0.0+ #4 PREEMPTLAZY\n  RIP: 0010:rmnet_vnd_rx_fixup (rmnet_vnd.c:27)\n  Call Trace:\n   <TASK>\n   __rmnet_map_ingress_handler (rmnet_handlers.c:48 rmnet_handlers.c:101)\n   rmnet_rx_handler (rmnet_handlers.c:129 rmnet_handlers.c:235)\n   __netif_receive_skb_core.constprop.0 (net/core/dev.c:6096)\n   __netif_receive_skb_one_core (net/core/dev.c:6208)\n   netif_receive_skb (net/core/dev.c:6467)\n   tun_get_user (drivers/net/tun.c:1955)\n   tun_chr_write_iter (drivers/net/tun.c:2003)\n   vfs_write (fs/read_write.c:688)\n   ksys_write (fs/read_write.c:740)\n   </TASK>\n\nAdd an rcu_head field to struct rmnet_endpoint and replace kfree() with\nkfree_rcu() so the endpoint memory remains valid through the RCU grace\nperiod. Also remove the rmnet_vnd_dellink() call and inline only the\nnr_rmnet_devs decrement, since rmnet_vnd_dellink() would set\nep->egress_dev to NULL during the grace period, creating a data race\nwith lockless readers.","publishedAt":"2026-07-20T16:27:47.216Z","updatedAt":"2026-08-05T12:39:57.703Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"c4e676c3505c5058922dc1a6f1ded795f6758135","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"9918698cf3aee4032e12bb42fd5a951dc465339b","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"310b93246bfec7d4452507e0c15477377ed9f025","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"1078ae8175777e80c9637996fb4a46c55f0ce576","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"41e06fcc5df0774d212e70c5b503fc769492bce3","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"8b17adf6d4fb6bf61fa4c3f58366a7c082799a71","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"f193e38cb257d033060b63f1cfd94af076b3a2ab","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"d00c953a8f69921f484b629801766da68f27f658","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c","drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.14","versionType":"semver"},{"version":"5.10.260","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.211","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.177","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.144","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.95","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.37","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.14","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c","drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h"]}],"references":["https://git.kernel.org/stable/c/c4e676c3505c5058922dc1a6f1ded795f6758135","https://git.kernel.org/stable/c/9918698cf3aee4032e12bb42fd5a951dc465339b","https://git.kernel.org/stable/c/310b93246bfec7d4452507e0c15477377ed9f025","https://git.kernel.org/stable/c/1078ae8175777e80c9637996fb4a46c55f0ce576","https://git.kernel.org/stable/c/41e06fcc5df0774d212e70c5b503fc769492bce3","https://git.kernel.org/stable/c/8b17adf6d4fb6bf61fa4c3f58366a7c082799a71","https://git.kernel.org/stable/c/f193e38cb257d033060b63f1cfd94af076b3a2ab","https://git.kernel.org/stable/c/d00c953a8f69921f484b629801766da68f27f658"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/64xxx/CVE-2026-64188.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64188","state":"PUBLISHED","datePublished":"2026-07-20T16:27:47.216Z","dateUpdated":"2026-08-05T12:39:57.703Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T07:54:57.040Z"},"containers":{"cna":{"title":"net: qualcomm: rmnet: fix endpoint use-after-free in rmnet_dellink()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: qualcomm: rmnet: fix endpoint use-after-free in rmnet_dellink()\n\nrmnet_dellink() removes the endpoint from the hash table with\nhlist_del_init_rcu() and then immediately frees it with kfree(). However,\nRCU readers on the receive path (rmnet_rx_handler ->\n__rmnet_map_ingress_handler) may still hold a reference to the endpoint and\ndereference ep->egress_dev after the memory has been freed. The endpoint is\na kmalloc-32 object, and the stale read at offset 8 corresponds to the\negress_dev pointer.\n\n  BUG: unable to handle page fault for address: ffffffffde942eef\n  Oops: 0002 [#1] SMP NOPTI\n  CPU: 1 UID: 0 PID: 137 Comm: poc_write Not tainted 7.0.0+ #4 PREEMPTLAZY\n  RIP: 0010:rmnet_vnd_rx_fixup (rmnet_vnd.c:27)\n  Call Trace:\n   <TASK>\n   __rmnet_map_ingress_handler (rmnet_handlers.c:48 rmnet_handlers.c:101)\n   rmnet_rx_handler (rmnet_handlers.c:129 rmnet_handlers.c:235)\n   __netif_receive_skb_core.constprop.0 (net/core/dev.c:6096)\n   __netif_receive_skb_one_core (net/core/dev.c:6208)\n   netif_receive_skb (net/core/dev.c:6467)\n   tun_get_user (drivers/net/tun.c:1955)\n   tun_chr_write_iter (drivers/net/tun.c:2003)\n   vfs_write (fs/read_write.c:688)\n   ksys_write (fs/read_write.c:740)\n   </TASK>\n\nAdd an rcu_head field to struct rmnet_endpoint and replace kfree() with\nkfree_rcu() so the endpoint memory remains valid through the RCU grace\nperiod. Also remove the rmnet_vnd_dellink() call and inline only the\nnr_rmnet_devs decrement, since rmnet_vnd_dellink() would set\nep->egress_dev to NULL during the grace period, creating a data race\nwith lockless readers."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"c4e676c3505c5058922dc1a6f1ded795f6758135","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"9918698cf3aee4032e12bb42fd5a951dc465339b","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"310b93246bfec7d4452507e0c15477377ed9f025","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"1078ae8175777e80c9637996fb4a46c55f0ce576","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"41e06fcc5df0774d212e70c5b503fc769492bce3","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"8b17adf6d4fb6bf61fa4c3f58366a7c082799a71","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"f193e38cb257d033060b63f1cfd94af076b3a2ab","versionType":"git"},{"version":"ceed73a2cf4aff2921802aa3d21d45280677547d","status":"affected","lessThan":"d00c953a8f69921f484b629801766da68f27f658","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c","drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.14","versionType":"semver"},{"version":"5.10.260","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.211","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.177","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.144","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.95","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.37","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.14","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c","drivers/net/ethernet/qualcomm/rmnet/rmnet_config.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/c4e676c3505c5058922dc1a6f1ded795f6758135"},{"url":"https://git.kernel.org/stable/c/9918698cf3aee4032e12bb42fd5a951dc465339b"},{"url":"https://git.kernel.org/stable/c/310b93246bfec7d4452507e0c15477377ed9f025"},{"url":"https://git.kernel.org/stable/c/1078ae8175777e80c9637996fb4a46c55f0ce576"},{"url":"https://git.kernel.org/stable/c/41e06fcc5df0774d212e70c5b503fc769492bce3"},{"url":"https://git.kernel.org/stable/c/8b17adf6d4fb6bf61fa4c3f58366a7c082799a71"},{"url":"https://git.kernel.org/stable/c/f193e38cb257d033060b63f1cfd94af076b3a2ab"},{"url":"https://git.kernel.org/stable/c/d00c953a8f69921f484b629801766da68f27f658"}],"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 - The complete exploit path is local: attacker-written frames enter through TUN while RTM_DELLINK over NETLINK_ROUTE invokes rmnet_dellink(); remote traffic alone cannot perform the required endpoint deletion.\nAC:L - The attacker controls both sides of the race by concurrently injecting crafted MAP frames and deleting or recreating the RMNET link, allowing repeated attempts without an uncontrollable condition.\nPR:L - Deletion requires CAP_NET_ADMIN in the route socket's network namespace, which an unprivileged user can obtain through a private user and network namespace to create TUN and RMNET devices.\nUI:N - No separate victim action is required because the attacker directly performs link setup, packet injection, and deletion.\nS:U - Exploitation compromises the kernel within the same security authority and does not cross a VM, IOMMU, or comparable scope boundary.\nC:H - The freed kmalloc-32 endpoint can be reclaimed with attacker-influenced contents, making the stale egress_dev pointer usable for forged-object dereferences and access to sensitive kernel memory.\nI:H - The corrupted egress_dev pointer reaches rmnet_vnd_rx_fixup, where derived per-CPU statistics pointers are written, providing a plausible path to arbitrary memory corruption and control-flow hijacking.\nA:H - The demonstrated race causes a page fault and kernel Oops in rmnet_vnd_rx_fixup, and it can be triggered repeatedly to crash the system."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:39:57.703Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"5.10.260"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"5.15.211"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"6.1.177"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"6.6.144"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"6.12.95"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"6.18.37"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"7.0.14"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"7.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}