CVE-2026-52994

In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: fix MSG_ZEROCOPY pinned-pages accounting virtio_transport_init_zcopy_skb() uses iter->count as the size argument for msg_zerocopy_realloc(), which in turn passes it to mm_account_pinned_pages() for RLIMIT_MEMLOCK accounting. However, this function is called after virtio_transport_fill_skb() has already consumed the iterator via __zerocopy_sg_from_iter(), so on the last skb, iter->count will be 0, skipping the RLIMIT_MEMLOCK enforcement. Pass pkt_len (the total bytes being sent) as an explicit parameter to virtio_transport_init_zcopy_skb() instead of reading the already-consumed iter->count. This matches TCP and UDP, which both call msg_zerocopy_realloc() with the original message size.

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/1cb36e252211506f51095fe7ced8286cc77b4c80	Patch
https://git.kernel.org/stable/c/6af1736b5810bc8a4a43a8518530113f5a757dc1	Patch
https://git.kernel.org/stable/c/d0117950075f0a9d5944980784c719d8ebcd4bff	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2026-06-24 17:17

Updated : 2026-07-15 13:09

NVD link : CVE-2026-52994

Mitre link : CVE-2026-52994

CVE.ORG link : CVE-2026-52994

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-Other

{"id": "CVE-2026-52994", "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": "581512a6dc939ef122e49336626ae159f3b8a345", "lessThan": "6af1736b5810bc8a4a43a8518530113f5a757dc1", "versionType": "git"}, {"status": "affected", "version": "581512a6dc939ef122e49336626ae159f3b8a345", "lessThan": "d0117950075f0a9d5944980784c719d8ebcd4bff", "versionType": "git"}, {"status": "affected", "version": "581512a6dc939ef122e49336626ae159f3b8a345", "lessThan": "1cb36e252211506f51095fe7ced8286cc77b4c80", "versionType": "git"}], "programFiles": ["net/vmw_vsock/virtio_transport_common.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.7"}, {"status": "unaffected", "version": "0", "lessThan": "6.7", "versionType": "semver"}, {"status": "unaffected", "version": "6.18.33", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.0.10", "versionType": "semver", "lessThanOrEqual": "7.0.*"}, {"status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/vmw_vsock/virtio_transport_common.c"], "defaultStatus": "affected"}]}], "published": "2026-06-24T17:17:10.327", "references": [{"url": "https://git.kernel.org/stable/c/1cb36e252211506f51095fe7ced8286cc77b4c80", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/6af1736b5810bc8a4a43a8518530113f5a757dc1", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/d0117950075f0a9d5944980784c719d8ebcd4bff", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-Other"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvsock/virtio: fix MSG_ZEROCOPY pinned-pages accounting\n\nvirtio_transport_init_zcopy_skb() uses iter->count as the size argument\nfor msg_zerocopy_realloc(), which in turn passes it to\nmm_account_pinned_pages() for RLIMIT_MEMLOCK accounting. However, this\nfunction is called after virtio_transport_fill_skb() has already consumed\nthe iterator via __zerocopy_sg_from_iter(), so on the last skb, iter->count\nwill be 0, skipping the RLIMIT_MEMLOCK enforcement.\n\nPass pkt_len (the total bytes being sent) as an explicit parameter to\nvirtio_transport_init_zcopy_skb() instead of reading the already-consumed\niter->count.\n\nThis matches TCP and UDP, which both call msg_zerocopy_realloc() with\nthe original message size."}], "lastModified": "2026-07-15T13:09:08.453", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5B5A3A3F-C424-4FA9-97E6-21FB07F5AA0D", "versionEndExcluding": "6.18.33", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A13475D2-59BF-4716-94B5-7C1D239A2CF4", "versionEndExcluding": "7.0.10", "versionStartIncluding": "6.19"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}