CVE-2026-52937

In the Linux kernel, the following vulnerability has been resolved: tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR In the SIOCGIFHWADDR path, tap_ioctl() copies 16 bytes of an uninitialised on-stack struct sockaddr_storage to userspace via ifr_hwaddr, but netif_get_mac_address() only writes sa_family and dev->addr_len (6 for Ethernet) bytes, leaving sa_data[6..13] uninitialised. Those 8 trailing bytes leak kernel stack contents; SIOCGIFHWADDR on a macvtap chardev returns kernel .text and direct-map pointers, defeating KASLR. Initialise ss at declaration.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/05305e832be7b9d65b2b72caacf7d850b3942b2a	Patch
https://git.kernel.org/stable/c/719007c3492f0f1f9e9cdbed8ac45ba45bb13eeb	Patch
https://git.kernel.org/stable/c/bddc09212c24934643bd44fc794748d2bbb3b6cd	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc1::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc2::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc3::::::
	cpe:2.3:o:linux:linux_kernel:7.1:rc4::::::

History

No history.

Information

Published : 2026-06-24 08:16

Updated : 2026-07-08 19:22

NVD link : CVE-2026-52937

Mitre link : CVE-2026-52937

CVE.ORG link : CVE-2026-52937

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-401

Missing Release of Memory after Effective Lifetime

{"id": "CVE-2026-52937", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "3b23a32a63219f51a5298bc55a65ecee866e79d0", "lessThan": "719007c3492f0f1f9e9cdbed8ac45ba45bb13eeb", "versionType": "git"}, {"status": "affected", "version": "3b23a32a63219f51a5298bc55a65ecee866e79d0", "lessThan": "05305e832be7b9d65b2b72caacf7d850b3942b2a", "versionType": "git"}, {"status": "affected", "version": "3b23a32a63219f51a5298bc55a65ecee866e79d0", "lessThan": "bddc09212c24934643bd44fc794748d2bbb3b6cd", "versionType": "git"}, {"status": "affected", "version": "176188cff67ec1aa55103647b61d02315cc38e98", "versionType": "git"}, {"status": "affected", "version": "1fc205d9e400f069ebf30d3faa6ec2bab2cbd7b4", "versionType": "git"}, {"status": "affected", "version": "4d0ae760c02c98fc78b78d3a0509896bc648ad1c", "versionType": "git"}, {"status": "affected", "version": "5.4.103", "lessThan": "5.5", "versionType": "semver"}, {"status": "affected", "version": "5.10.21", "lessThan": "5.11", "versionType": "semver"}, {"status": "affected", "version": "5.11.4", "lessThan": "5.12", "versionType": "semver"}], "programFiles": ["drivers/net/tap.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.12"}, {"status": "unaffected", "version": "0", "lessThan": "5.12", "versionType": "semver"}, {"status": "unaffected", "version": "6.18.34", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.0.11", "versionType": "semver", "lessThanOrEqual": "7.0.*"}, {"status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["drivers/net/tap.c"], "defaultStatus": "affected"}]}], "published": "2026-06-24T08:16:23.980", "references": [{"url": "https://git.kernel.org/stable/c/05305e832be7b9d65b2b72caacf7d850b3942b2a", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/719007c3492f0f1f9e9cdbed8ac45ba45bb13eeb", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/bddc09212c24934643bd44fc794748d2bbb3b6cd", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-401"}]}], "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."}], "lastModified": "2026-07-08T19:22:42.793", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "77F47A48-724C-4A8A-BE16-F2C832EECA05", "versionEndExcluding": "5.5", "versionStartIncluding": "5.4.103"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FA8451E2-8B08-45A9-AEC4-3F6C9C651E35", "versionEndExcluding": "5.11", "versionStartIncluding": "5.10.21"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0B6E32E7-34D9-4D94-B9F6-8D3A2D90FF06", "versionEndExcluding": "6.18.34", "versionStartIncluding": "5.11.4"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0520D091-FC52-4A50-AF07-70AE7D08B750", "versionEndExcluding": "7.0.11", "versionStartIncluding": "6.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0D38F0BF-A728-4133-A358-D44A2F7EE6D6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "EC732D08-5F7B-46D9-B154-E60C7F4F0A97"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E5910A9D-F60A-409A-B486-FE66BFEBA9B9"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}