{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-23254", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-01-13T15:37:45.990Z", "datePublished": "2026-03-18T17:41:00.591Z", "dateUpdated": "2026-05-23T16:04:21.918Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-23T16:04:21.918Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: gro: fix outer network offset\n\nThe udp GRO complete stage assumes that all the packets inserted the RX\nhave the `encapsulation` flag zeroed. Such assumption is not true, as a\nfew H/W NICs can set such flag when H/W offloading the checksum for\nan UDP encapsulated traffic, the tun driver can inject GSO packets with\nUDP encapsulation and the problematic layout can also be created via\na veth based setup.\n\nDue to the above, in the problematic scenarios, udp4_gro_complete() uses\nthe wrong network offset (inner instead of outer) to compute the outer\nUDP header pseudo checksum, leading to csum validation errors later on\nin packet processing.\n\nAddress the issue always clearing the encapsulation flag at GRO completion\ntime. Such flag will be set again as needed for encapsulated packets by\nudp_gro_complete()."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/core/gro.c"], "versions": [{"version": "af276a5ac8e938c8b058e3e124073cc1e322d98b", "lessThan": "9d40a85138568696387ef04cd004c64612a70874", "status": "affected", "versionType": "git"}, {"version": "5ef31ea5d053a8f493a772ebad3f3ce82c35d845", "lessThan": "b83557bc6f560433fe5d727e241069f8db5ba709", "status": "affected", "versionType": "git"}, {"version": "5ef31ea5d053a8f493a772ebad3f3ce82c35d845", "lessThan": "2e5edb69e5d0e23ef248c56fc977039268c77a7b", "status": "affected", "versionType": "git"}, {"version": "5ef31ea5d053a8f493a772ebad3f3ce82c35d845", "lessThan": "5c2c3c38be396257a6a2e55bd601a12bb9781507", "status": "affected", "versionType": "git"}, {"version": "dbd9466d323a72e22efe09151253d195d36d3bf6", "status": "affected", "versionType": "git"}, {"version": "6.6.31", "lessThan": "6.6.124", "status": "affected", "versionType": "semver"}, {"version": "6.8.10", "lessThan": "6.9", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/core/gro.c"], "versions": [{"version": "6.9", "status": "affected"}, {"version": "0", "lessThan": "6.9", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.124", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.70", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.10", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.31", "versionEndExcluding": "6.6.124"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.12.70"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.18.10"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.9", "versionEndExcluding": "6.19"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8.10"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/9d40a85138568696387ef04cd004c64612a70874"}, {"url": "https://git.kernel.org/stable/c/b83557bc6f560433fe5d727e241069f8db5ba709"}, {"url": "https://git.kernel.org/stable/c/2e5edb69e5d0e23ef248c56fc977039268c77a7b"}, {"url": "https://git.kernel.org/stable/c/5c2c3c38be396257a6a2e55bd601a12bb9781507"}], "title": "net: gro: fix outer network offset", "x_generator": {"engine": "bippy-1.2.0"}}}}

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{"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "7227C1EF-FAE4-4A81-A334-1487EFCBF507", "versionEndExcluding": "6.6.124", "versionStartIncluding": "6.6.31", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "DD26A649-FB0B-4A7B-A16B-A9D27807D7E9", "versionEndExcluding": "6.9", "versionStartIncluding": "6.8.10", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "389604B3-C4AF-4558-AE99-65329C545794", "versionEndExcluding": "6.12.70", "versionStartIncluding": "6.9.1", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "7156C23F-009E-4D05-838C-A2DA417B5B8D", "versionEndExcluding": "6.18.10", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.9:-:*:*:*:*:*:*", "matchCriteriaId": "3F2A4A3D-068A-4CF2-A09F-9C7937DDB0A5", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.9:rc7:*:*:*:*:*:*", "matchCriteriaId": "DAECDCD8-F556-4606-8D7B-5C6D47A501F2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*", "matchCriteriaId": "17B67AA7-40D6-4AFA-8459-F200F3D7CFD1", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*", "matchCriteriaId": "C47E4CC9-C826-4FA9-B014-7FE3D9B318B2", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*", "matchCriteriaId": "F71D92C0-C023-48BD-B3B6-70B638EEE298", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*", "matchCriteriaId": "13580667-0A98-40CC-B29F-D12790B91BDB", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:*", "matchCriteriaId": "CAD1FED7-CF48-47BF-AC7D-7B6FA3C065FC", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:*", "matchCriteriaId": "3EF854A1-ABB1-4E93-BE9A-44569EC76C0D", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc7:*:*:*:*:*:*", "matchCriteriaId": "F5DC0CA6-F0AF-4DDF-A882-3DADB9A886A7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc8:*:*:*:*:*:*", "matchCriteriaId": "EB5B7DFC-C36B-45D8-922C-877569FDDF43", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: gro: fix outer network offset\n\nThe udp GRO complete stage assumes that all the packets inserted the RX\nhave the `encapsulation` flag zeroed. Such assumption is not true, as a\nfew H/W NICs can set such flag when H/W offloading the checksum for\nan UDP encapsulated traffic, the tun driver can inject GSO packets with\nUDP encapsulation and the problematic layout can also be created via\na veth based setup.\n\nDue to the above, in the problematic scenarios, udp4_gro_complete() uses\nthe wrong network offset (inner instead of outer) to compute the outer\nUDP header pseudo checksum, leading to csum validation errors later on\nin packet processing.\n\nAddress the issue always clearing the encapsulation flag at GRO completion\ntime. Such flag will be set again as needed for encapsulated packets by\nudp_gro_complete()."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet: gro: corregir desplazamiento de red externo\n\nLa etapa de completado de GRO de UDP asume que todos los paquetes insertados en el RX tienen el indicador 'encapsulation' puesto a cero. Dicha suposici\u00f3n no es cierta, ya que algunas NIC de H/W pueden establecer dicho indicador al descargar el checksum por H/W para un tr\u00e1fico UDP encapsulado, el controlador tun puede inyectar paquetes GSO con encapsulaci\u00f3n UDP y la disposici\u00f3n problem\u00e1tica tambi\u00e9n puede crearse a trav\u00e9s de una configuraci\u00f3n basada en veth.\n\nDebido a lo anterior, en los escenarios problem\u00e1ticos, udp4_gro_complete() utiliza el desplazamiento de red incorrecto (interno en lugar de externo) para calcular el pseudo checksum del encabezado UDP externo, lo que lleva a errores de validaci\u00f3n de csum m\u00e1s adelante en el procesamiento de paquetes.\n\nAbordar el problema siempre borrando el indicador de encapsulaci\u00f3n en el momento de completado de GRO. Dicho indicador se establecer\u00e1 de nuevo seg\u00fan sea necesario para paquetes encapsulados por udp_gro_complete()."}], "id": "CVE-2026-23254", "lastModified": "2026-06-01T14:10:37.893", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2026-03-18T18:16:23.530", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2e5edb69e5d0e23ef248c56fc977039268c77a7b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/5c2c3c38be396257a6a2e55bd601a12bb9781507"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/9d40a85138568696387ef04cd004c64612a70874"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/b83557bc6f560433fe5d727e241069f8db5ba709"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: net: gro: fix outer network offset", "id": "2448699", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2448699"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "details": ["No description is available for this CVE."], "name": "CVE-2026-23254", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-03-18T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-23254\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-23254\nhttps://lore.kernel.org/linux-cve-announce/2026031817-CVE-2026-23254-6387@gregkh/T"], "threat_severity": "Low"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[af276a5ac8e938c8b058e3e124073cc1e322d98b,9d40a85138568696387ef04cd004c64612a70874)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ef31ea5d053a8f493a772ebad3f3ce82c35d845,b83557bc6f560433fe5d727e241069f8db5ba709)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ef31ea5d053a8f493a772ebad3f3ce82c35d845,2e5edb69e5d0e23ef248c56fc977039268c77a7b)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ef31ea5d053a8f493a772ebad3f3ce82c35d845,5c2c3c38be396257a6a2e55bd601a12bb9781507)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[dbd9466d323a72e22efe09151253d195d36d3bf6,*]"}}], "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": "6.9"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,6.9)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.124,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.70,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.10,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.19,*]"}}], "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"}], "analysis": {"en": {"generated_at": "2026-03-27T11:24:36.937627+00:00", "value": {"mitigation_remediation": ["Apply a Linux kernel update that includes the net: gro: fix outer network offset patch. Reboot the system after upgrading to ensure the new kernel is running."], "summary": {"action": "Patch", "impact": "Denial of Service"}, "threat_synthesis": {"affected_systems": "All Linux kernel builds that employ the Ethernet GRO path and support UDP checksum offloading are affected. The vulnerability applies to standard distribution kernels and any custom kernel configurations that enable GRO, including those using NICs that set the encapsulation flag or the tun/virtual Ethernet drivers that inject GSO packets. No specific version range is documented, but the fix has been merged into the kernel trunk and will be propagated through subsequent kernel releases. Systems should verify whether they are running a kernel version that contains the patch committing this fix.", "description_and_impact": "A defect in the Linux kernel\u2019s Generic Receive Offload (GRO) module causes the UDP checksum calculation to use an incorrect network offset when certain network interfaces set an encapsulation flag during offloading. The resulting checksum computation errors prevent packets from passing later validation steps, potentially leading to dropped or rejected traffic. This error can disrupt network communication for affected hosts, representing a modest Denial of Service risk. The weakness arises from improper handling of the encapsulation flag and incorrect offset usage, which aligns with known checksum calculation flaws in networking code.", "risk_and_exploitability": "The CVSS score of 5.5 indicates moderate severity, and the EPSS score of less than 1% denotes a low likelihood of current exploitation. The vulnerability is not listed in the CISA KEV catalog. Exploitation would require an attacker to deliver specially crafted UDP traffic or to manipulate NIC offloading behavior to trigger the incorrect checksum path. Such attacks are feasible over the network, but for most environments the probability of successful exploitation remains low given the minimal impact beyond packet loss or service interruption."}}}}, "created": "2026-03-19T08:56:12.460728+00:00", "updated": "2026-03-27T15:48:24.393266+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}