CVE-2025-40279 (GCVE-0-2025-40279)

Vulnerability from cvelistv5 – Published: 2025-12-06 21:51 – Updated: 2026-05-11 21:46
VLAI
Title
net: sched: act_connmark: initialize struct tc_ife to fix kernel leak
Summary
In the Linux kernel, the following vulnerability has been resolved: net: sched: act_connmark: initialize struct tc_ife to fix kernel leak In tcf_connmark_dump(), the variable 'opt' was partially initialized using a designatied initializer. While the padding bytes are reamined uninitialized. nla_put() copies the entire structure into a netlink message, these uninitialized bytes leaked to userspace. Initialize the structure with memset before assigning its fields to ensure all members and padding are cleared prior to beign copied.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 7061 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 22a5dc0e5e3e8fef804230cd73ed7b0afd4c7bae , < 218b67c8c8246d47a2a7910eae80abe4861fe2b7 (git)
Affected: 22a5dc0e5e3e8fef804230cd73ed7b0afd4c7bae , < 73cc56c608c209d3d666cc571293b090a471da70 (git)
Affected: 22a5dc0e5e3e8fef804230cd73ed7b0afd4c7bae , < 31e4aa93e2e5b5647fc235b0f6ee329646878f9e (git)
Affected: 22a5dc0e5e3e8fef804230cd73ed7b0afd4c7bae , < 51cb05d4fd632596816ba44e882e84db9fb28a7e (git)
Affected: 22a5dc0e5e3e8fef804230cd73ed7b0afd4c7bae , < 25837889ec062f2b7618142cd80253dff3da5343 (git)
Affected: 22a5dc0e5e3e8fef804230cd73ed7b0afd4c7bae , < 62b656e43eaeae445a39cd8021a4f47065af4389 (git)
guessed Create a notification for this product.
Linux Linux Affected: 4.0
Unaffected: 0 , < 4.0 (semver)
Unaffected: 5.15.197 , ≤ 5.15.* (semver)
Unaffected: 6.1.159 , ≤ 6.1.* (semver)
Unaffected: 6.6.117 , ≤ 6.6.* (semver)
Unaffected: 6.12.59 , ≤ 6.12.* (semver)
Unaffected: 6.17.9 , ≤ 6.17.* (semver)
Unaffected: 6.18 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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{
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          "programFiles": [
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      "cpeApplicability": [
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sched: act_connmark: initialize struct tc_ife to fix kernel leak\n\nIn tcf_connmark_dump(), the variable \u0027opt\u0027 was partially initialized using a\ndesignatied initializer. While the padding bytes are reamined\nuninitialized. nla_put() copies the entire structure into a\nnetlink message, these uninitialized bytes leaked to userspace.\n\nInitialize the structure with memset before assigning its fields\nto ensure all members and padding are cleared prior to beign copied."
        }
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      "providerMetadata": {
        "dateUpdated": "2026-05-11T21:46:16.602Z",
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        "shortName": "Linux"
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        },
        {
          "url": "https://git.kernel.org/stable/c/62b656e43eaeae445a39cd8021a4f47065af4389"
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    "cveId": "CVE-2025-40279",
    "datePublished": "2025-12-06T21:51:03.010Z",
    "dateReserved": "2025-04-16T07:20:57.184Z",
    "dateUpdated": "2026-05-11T21:46:16.602Z",
    "state": "PUBLISHED"
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sched: act_connmark: initialize struct tc_ife to fix kernel leak\n\nIn tcf_connmark_dump(), the variable \u0027opt\u0027 was partially initialized using a\ndesignatied initializer. While the padding bytes are reamined\nuninitialized. nla_put() copies the entire structure into a\nnetlink message, these uninitialized bytes leaked to userspace.\n\nInitialize the structure with memset before assigning its fields\nto ensure all members and padding are cleared prior to beign copied."
          },
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            "lang": "es",
            "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet: sched: act_connmark: inicializar la estructura tc_ife para corregir una fuga del kernel\n\nEn tcf_connmark_dump(), la variable \u0027opt\u0027 fue inicializada parcialmente usando un inicializador designado. Mientras que los bytes de relleno permanecieron sin inicializar. nla_put() copia la estructura completa en un mensaje netlink, estos bytes sin inicializar se filtraron al espacio de usuario.\n\nInicializar la estructura con memset antes de asignar sus campos para asegurar que todos los miembros y el relleno se borren antes de ser copiados."
          }
        ],
        "id": "CVE-2025-40279",
        "lastModified": "2026-10-15T19:10:00.173",
        "metrics": {},
        "published": "2025-12-06T22:15:55.843",
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      "title": "kernel: Linux kernel: Information disclosure via uninitialized data in tcf_connmark_dump()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-40279.json",
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    }
  }
}



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