{"id":"CVE-2026-52937","state":"PUBLISHED","title":"tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR\n\nIn the SIOCGIFHWADDR path, tap_ioctl() copies 16 bytes of an\nuninitialised on-stack struct sockaddr_storage to userspace via\nifr_hwaddr, but netif_get_mac_address() only writes sa_family and\ndev->addr_len (6 for Ethernet) bytes, leaving sa_data[6..13] uninitialised.\n\nThose 8 trailing bytes leak kernel stack contents; SIOCGIFHWADDR on a\nmacvtap chardev returns kernel .text and direct-map pointers, defeating\nKASLR.\n\nInitialise ss at declaration.","publishedAt":"2026-06-24T07:14:27.305Z","updatedAt":"2026-10-30T12:26:20.549Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"4b6dcfe0e3dfffd8057a4fc99b3f096c45709905","versionType":"git"},{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"37d028a473b0826ad5970b52b791db4a29a23627","versionType":"git"},{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"8197905d97099d8b1e3883112bbb497abd20f9f0","versionType":"git"},{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"719007c3492f0f1f9e9cdbed8ac45ba45bb13eeb","versionType":"git"},{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"05305e832be7b9d65b2b72caacf7d850b3942b2a","versionType":"git"},{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"bddc09212c24934643bd44fc794748d2bbb3b6cd","versionType":"git"},{"version":"176188cff67ec1aa55103647b61d02315cc38e98","status":"affected","versionType":"git"},{"version":"1fc205d9e400f069ebf30d3faa6ec2bab2cbd7b4","status":"affected","versionType":"git"},{"version":"4d0ae760c02c98fc78b78d3a0509896bc648ad1c","status":"affected","versionType":"git"},{"version":"5.4.103","status":"affected","lessThan":"5.5","versionType":"semver"},{"version":"5.10.21","status":"affected","lessThan":"5.11","versionType":"semver"},{"version":"5.11.4","status":"affected","lessThan":"5.12","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/tap.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.12","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.114","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.34","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.11","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/tap.c"]}],"references":["https://git.kernel.org/stable/c/4b6dcfe0e3dfffd8057a4fc99b3f096c45709905","https://git.kernel.org/stable/c/37d028a473b0826ad5970b52b791db4a29a23627","https://git.kernel.org/stable/c/8197905d97099d8b1e3883112bbb497abd20f9f0","https://git.kernel.org/stable/c/719007c3492f0f1f9e9cdbed8ac45ba45bb13eeb","https://git.kernel.org/stable/c/05305e832be7b9d65b2b72caacf7d850b3942b2a","https://git.kernel.org/stable/c/bddc09212c24934643bd44fc794748d2bbb3b6cd"],"weaknesses":[],"ingestedAt":"2026-10-30T12:44:04.813Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/52xxx/CVE-2026-52937.json","commit":"db8103c5921aac81d5d90efcf3745980dafabf49","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-52937","state":"PUBLISHED","datePublished":"2026-06-24T07:14:27.305Z","dateUpdated":"2026-10-30T12:26:20.549Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-06-09T07:44:35.370Z"},"containers":{"cna":{"title":"tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR\n\nIn the SIOCGIFHWADDR path, tap_ioctl() copies 16 bytes of an\nuninitialised on-stack struct sockaddr_storage to userspace via\nifr_hwaddr, but netif_get_mac_address() only writes sa_family and\ndev->addr_len (6 for Ethernet) bytes, leaving sa_data[6..13] uninitialised.\n\nThose 8 trailing bytes leak kernel stack contents; SIOCGIFHWADDR on a\nmacvtap chardev returns kernel .text and direct-map pointers, defeating\nKASLR.\n\nInitialise ss at declaration."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"4b6dcfe0e3dfffd8057a4fc99b3f096c45709905","versionType":"git"},{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"37d028a473b0826ad5970b52b791db4a29a23627","versionType":"git"},{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"8197905d97099d8b1e3883112bbb497abd20f9f0","versionType":"git"},{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"719007c3492f0f1f9e9cdbed8ac45ba45bb13eeb","versionType":"git"},{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"05305e832be7b9d65b2b72caacf7d850b3942b2a","versionType":"git"},{"version":"3b23a32a63219f51a5298bc55a65ecee866e79d0","status":"affected","lessThan":"bddc09212c24934643bd44fc794748d2bbb3b6cd","versionType":"git"},{"version":"176188cff67ec1aa55103647b61d02315cc38e98","status":"affected","versionType":"git"},{"version":"1fc205d9e400f069ebf30d3faa6ec2bab2cbd7b4","status":"affected","versionType":"git"},{"version":"4d0ae760c02c98fc78b78d3a0509896bc648ad1c","status":"affected","versionType":"git"},{"version":"5.4.103","status":"affected","lessThan":"5.5","versionType":"semver"},{"version":"5.10.21","status":"affected","lessThan":"5.11","versionType":"semver"},{"version":"5.11.4","status":"affected","lessThan":"5.12","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/tap.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.12","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.114","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.34","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.11","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/tap.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/4b6dcfe0e3dfffd8057a4fc99b3f096c45709905"},{"url":"https://git.kernel.org/stable/c/37d028a473b0826ad5970b52b791db4a29a23627"},{"url":"https://git.kernel.org/stable/c/8197905d97099d8b1e3883112bbb497abd20f9f0"},{"url":"https://git.kernel.org/stable/c/719007c3492f0f1f9e9cdbed8ac45ba45bb13eeb"},{"url":"https://git.kernel.org/stable/c/05305e832be7b9d65b2b72caacf7d850b3942b2a"},{"url":"https://git.kernel.org/stable/c/bddc09212c24934643bd44fc794748d2bbb3b6cd"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:26:20.549Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.12.114"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.18.34"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"7.0.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"7.1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4.103"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10.21"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.11.4"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}