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{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/openvswitch/actions.c", "net/openvswitch/datapath.c", "net/openvswitch/datapath.h", "net/openvswitch/vport.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "50a6a85f3d6b1d22d8436848606cdef5d2c490b4", "status": "affected", "version": "f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1", "versionType": "git"}, {"lessThan": "2623c48cc3a8da9a1886fd8f65c0e348f4406fd6", "status": "affected", "version": "f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1", "versionType": "git"}, {"lessThan": "e211b081901ffca76674082c73eeaed53524c369", "status": "affected", "version": "f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1", "versionType": "git"}, {"lessThan": "a16eaaf7c0b0ccdef6166707d90ffbc6eebf6855", "status": "affected", "version": "f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1", "versionType": "git"}, {"lessThan": "fbfa3ad2ad6f3a5624aba5211c46290fb98cc9dc", "status": "affected", "version": "f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1", "versionType": "git"}, {"lessThan": "100a23b1613e9218e0af654ef102352c713f0263", "status": "affected", "version": "f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1", "versionType": "git"}, {"lessThan": "ea85dbcbe8d4056ecb54352f97743d138ea4c407", "status": "affected", "version": "f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1", "versionType": "git"}, {"lessThan": "4032f8ed10fcb84d41c508dfb04be96589f78dfe", "status": "affected", "version": "f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/openvswitch/actions.c", "net/openvswitch/datapath.c", "net/openvswitch/datapath.h", "net/openvswitch/vport.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "4.8"}, {"lessThan": "4.8", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.265", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.216", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.183", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.148", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.101", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.42", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.6", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nopenvswitch: fix GSO userspace truncation underflow\n\nOVS_ACTION_ATTR_TRUNC currently stores a delta from the original skb\nlength in OVS_CB(skb)->cutlen. When a later userspace action segments a\nGSO skb, queue_gso_packets() reuses that delta for each smaller segment.\nA segment can then reach queue_userspace_packet() with cutlen greater\nthan skb->len, underflowing the length passed to skb_zerocopy().\n\nStore the maximum preserved length instead and bound each consumer\nagainst the current skb length. Use U32_MAX as the no-truncation\nsentinel so the value remains valid if skb geometry changes before a\nconsumer handles it."}], "id": "CVE-2026-68123", "lastModified": "2026-10-19T21:17:52.287", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-68123", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-16T15:44:13.520896Z", "version": "2.0.3"}}]}, "published": "2026-08-10T13:19:57.427", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/100a23b1613e9218e0af654ef102352c713f0263"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/2623c48cc3a8da9a1886fd8f65c0e348f4406fd6"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4032f8ed10fcb84d41c508dfb04be96589f78dfe"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/50a6a85f3d6b1d22d8436848606cdef5d2c490b4"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a16eaaf7c0b0ccdef6166707d90ffbc6eebf6855"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e211b081901ffca76674082c73eeaed53524c369"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/ea85dbcbe8d4056ecb54352f97743d138ea4c407"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/fbfa3ad2ad6f3a5624aba5211c46290fb98cc9dc"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-191"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "kernel: openvswitch: fix GSO userspace truncation underflow", "id": "2513451", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2513451"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-787", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nopenvswitch: fix GSO userspace truncation underflow\nOVS_ACTION_ATTR_TRUNC currently stores a delta from the original skb\nlength in OVS_CB(skb)->cutlen. When a later userspace action segments a\nGSO skb, queue_gso_packets() reuses that delta for each smaller segment.\nA segment can then reach queue_userspace_packet() with cutlen greater\nthan skb->len, underflowing the length passed to skb_zerocopy().\nStore the maximum preserved length instead and bound each consumer\nagainst the current skb length. Use U32_MAX as the no-truncation\nsentinel so the value remains valid if skb geometry changes before a\nconsumer handles it.", "A flaw was found in the Open vSwitch component of the Linux kernel. This vulnerability arises from an underflow condition when handling Generic Segmentation Offload (GSO) packets in userspace. A length calculation error can lead to a buffer underflow when data is processed by the `skb_zerocopy()` function. This issue could result in memory corruption, potentially leading to a denial of service or other unpredictable system behavior."], "name": "CVE-2026-68123", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Under investigation", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:enterprise_linux_nvidia:", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux for NVIDIA 26"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Affected", "package_name": "rhcos", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-08-10T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-68123\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-68123\nhttps://lore.kernel.org/linux-cve-announce/2026081056-CVE-2026-68123-49d8@gregkh/T"], "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1,a16eaaf7c0b0ccdef6166707d90ffbc6eebf6855)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1,fbfa3ad2ad6f3a5624aba5211c46290fb98cc9dc)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1,100a23b1613e9218e0af654ef102352c713f0263)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1,ea85dbcbe8d4056ecb54352f97743d138ea4c407)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f2a4d086ed4c588d32fe9b7aa67fead7280e7bf1,4032f8ed10fcb84d41c508dfb04be96589f78dfe)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "4.8"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,4.8)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.148,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.101,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.42,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.6,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-rc5,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-08-10T13:45:03.571558+00:00", "updated": "2026-10-20T05:00:16.569499+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}