GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2026-74288 (GCVE-0-2026-74288)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:57 – Updated: 2026-08-17 05:45
VLAI
Title
net: fib_rules: Don't dump dying fib_rule in fib_rules_dump().
Summary
In the Linux kernel, the following vulnerability has been resolved: net: fib_rules: Don't dump dying fib_rule in fib_rules_dump(). rocker_router_fib_event() calls fib_rule_get() during RCU dump. If the fib_rule is dying, refcount_inc() will complain about it. Let's call refcount_inc_not_zero() in fib_rules_dump().
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 5d7bfd141924a5ece21eb612ad3c56612f041c1e , < 0f929b59f4cd0e05bb1ecefe12b77e85911d4be2 (git)
Affected: 5d7bfd141924a5ece21eb612ad3c56612f041c1e , < 4b7ae30c81c2ee10a644749a3704a5c797ccc308 (git)
Affected: 5d7bfd141924a5ece21eb612ad3c56612f041c1e , < 2dfdc210d240bd48bb2ea746430b02b5571b6db9 (git)
Affected: 5d7bfd141924a5ece21eb612ad3c56612f041c1e , < a7ef30753353ba6a95d693b1863a0214222a199a (git)
Affected: 5d7bfd141924a5ece21eb612ad3c56612f041c1e , < 1fbc6c6efe78f4454a51afa0587efb6826f60f00 (git)
Affected: 5d7bfd141924a5ece21eb612ad3c56612f041c1e , < bb4a5b3c91af3c8d705bb2e9f6f8069a70db26fc (git)
Affected: 5d7bfd141924a5ece21eb612ad3c56612f041c1e , < 3af0bc1bd9039e2e50abf3e2d7fee411f38bce4e (git)
Affected: 5d7bfd141924a5ece21eb612ad3c56612f041c1e , < 2821e85c058f81c9948a2fb1a634f7b47457d51c (git)
guessed Create a notification for this product.
Linux Linux Affected: 4.12
Unaffected: 0 , < 4.12 (semver)
Unaffected: 5.10.261 , ≤ 5.10.* (semver)
Unaffected: 5.15.212 , ≤ 5.15.* (semver)
Unaffected: 6.1.178 , ≤ 6.1.* (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.97 , ≤ 6.12.* (semver)
Unaffected: 6.18.40 , ≤ 6.18.* (semver)
Unaffected: 7.1.5 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/net/fib_rules.h",
            "net/core/fib_rules.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "0f929b59f4cd0e05bb1ecefe12b77e85911d4be2",
              "status": "affected",
              "version": "5d7bfd141924a5ece21eb612ad3c56612f041c1e",
              "versionType": "git"
            },
            {
              "lessThan": "4b7ae30c81c2ee10a644749a3704a5c797ccc308",
              "status": "affected",
              "version": "5d7bfd141924a5ece21eb612ad3c56612f041c1e",
              "versionType": "git"
            },
            {
              "lessThan": "2dfdc210d240bd48bb2ea746430b02b5571b6db9",
              "status": "affected",
              "version": "5d7bfd141924a5ece21eb612ad3c56612f041c1e",
              "versionType": "git"
            },
            {
              "lessThan": "a7ef30753353ba6a95d693b1863a0214222a199a",
              "status": "affected",
              "version": "5d7bfd141924a5ece21eb612ad3c56612f041c1e",
              "versionType": "git"
            },
            {
              "lessThan": "1fbc6c6efe78f4454a51afa0587efb6826f60f00",
              "status": "affected",
              "version": "5d7bfd141924a5ece21eb612ad3c56612f041c1e",
              "versionType": "git"
            },
            {
              "lessThan": "bb4a5b3c91af3c8d705bb2e9f6f8069a70db26fc",
              "status": "affected",
              "version": "5d7bfd141924a5ece21eb612ad3c56612f041c1e",
              "versionType": "git"
            },
            {
              "lessThan": "3af0bc1bd9039e2e50abf3e2d7fee411f38bce4e",
              "status": "affected",
              "version": "5d7bfd141924a5ece21eb612ad3c56612f041c1e",
              "versionType": "git"
            },
            {
              "lessThan": "2821e85c058f81c9948a2fb1a634f7b47457d51c",
              "status": "affected",
              "version": "5d7bfd141924a5ece21eb612ad3c56612f041c1e",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "include/net/fib_rules.h",
            "net/core/fib_rules.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.12"
            },
            {
              "lessThan": "4.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.261",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.212",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.261",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.212",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.178",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.145",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "4.12",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: fib_rules: Don\u0027t dump dying fib_rule in fib_rules_dump().\n\nrocker_router_fib_event() calls fib_rule_get() during RCU dump.\n\nIf the fib_rule is dying, refcount_inc() will complain about it.\n\nLet\u0027s call refcount_inc_not_zero() in fib_rules_dump()."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The bug is reached only through local kernel networking control paths: fib_rules_dump() runs during register_fib_notifier() and races with RTM_DELRULE netlink handling in fib_delrule(), not via remotely received packets or a network-facing protocol handler.\nAC:L - Exploitation is a race where the attacker concurrently deletes FIB rules (repeated RTM_DELRULE or netns teardown) while fib_rules_dump() replays RULE_ADD events; the attacker controls both sides and can retry, as demonstrated by syzbot during netdevsim reload/cleanup_net.\nPR:L - Triggering concurrent FIB rule deletion requires CAP_NET_ADMIN on the target network namespace, which unprivileged users can obtain inside user/network namespaces (e.g., unshare -Urn), while driver registration commonly occurs in the same namespace during netdevsim/devlink setup.\nUI:N - No end-user or administrator UI action is required beyond programmatic netlink/devlink operations that an attacker can script; exploitation does not depend on a victim opening files, clicking links, or mounting filesystems.\nS:U - Impact is a kernel heap use-after-free in fib_rule handling leading to memory corruption within the host kernel; it does not inherently cross a VM/hypervisor or IOMMU security boundary without separate exploitation of unrelated boundaries.\nC:H - A dying fib_rule can be passed to FIB notifiers after its refcount hits zero; handlers such as rocker_router_fib_event() call fib_rule_get() and later dereference rule fields in workqueues, enabling reads of freed slab memory and potential kernel pointer disclosure.\nI:H - The UAF hands attackers control over the lifetime and contents of freed fib_rule objects; with heap grooming this class of corruption is reasonably leveraged into arbitrary kernel writes or control-flow hijack, not merely a benign warning.\nA:H - refcount_inc() on a zero refcount emits use-after-free warnings and concurrent dereference of freed fib_rule structures during dump/replay can cause kernel oops/panics, especially under automated stress seen in syzbot reproductions."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:45:27.821Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/0f929b59f4cd0e05bb1ecefe12b77e85911d4be2"
        },
        {
          "url": "https://git.kernel.org/stable/c/4b7ae30c81c2ee10a644749a3704a5c797ccc308"
        },
        {
          "url": "https://git.kernel.org/stable/c/2dfdc210d240bd48bb2ea746430b02b5571b6db9"
        },
        {
          "url": "https://git.kernel.org/stable/c/a7ef30753353ba6a95d693b1863a0214222a199a"
        },
        {
          "url": "https://git.kernel.org/stable/c/1fbc6c6efe78f4454a51afa0587efb6826f60f00"
        },
        {
          "url": "https://git.kernel.org/stable/c/bb4a5b3c91af3c8d705bb2e9f6f8069a70db26fc"
        },
        {
          "url": "https://git.kernel.org/stable/c/3af0bc1bd9039e2e50abf3e2d7fee411f38bce4e"
        },
        {
          "url": "https://git.kernel.org/stable/c/2821e85c058f81c9948a2fb1a634f7b47457d51c"
        }
      ],
      "title": "net: fib_rules: Don\u0027t dump dying fib_rule in fib_rules_dump().",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74288",
    "datePublished": "2026-08-15T05:57:55.760Z",
    "dateReserved": "2026-08-15T05:44:03.881Z",
    "dateUpdated": "2026-08-17T05:45:27.821Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-74288",
      "date": "2026-09-05",
      "epss": "0.00129",
      "percentile": "0.0287"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-74288\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-08-15T06:22:28.343\",\"lastModified\":\"2026-08-17T06:19:22.723\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnet: fib_rules: Don\u0027t dump dying fib_rule in fib_rules_dump().\\n\\nrocker_router_fib_event() calls fib_rule_get() during RCU dump.\\n\\nIf the fib_rule is dying, refcount_inc() will complain about it.\\n\\nLet\u0027s call refcount_inc_not_zero() in fib_rules_dump().\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"include/net/fib_rules.h\",\"net/core/fib_rules.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5d7bfd141924a5ece21eb612ad3c56612f041c1e\",\"lessThan\":\"0f929b59f4cd0e05bb1ecefe12b77e85911d4be2\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5d7bfd141924a5ece21eb612ad3c56612f041c1e\",\"lessThan\":\"4b7ae30c81c2ee10a644749a3704a5c797ccc308\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5d7bfd141924a5ece21eb612ad3c56612f041c1e\",\"lessThan\":\"2dfdc210d240bd48bb2ea746430b02b5571b6db9\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5d7bfd141924a5ece21eb612ad3c56612f041c1e\",\"lessThan\":\"a7ef30753353ba6a95d693b1863a0214222a199a\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5d7bfd141924a5ece21eb612ad3c56612f041c1e\",\"lessThan\":\"1fbc6c6efe78f4454a51afa0587efb6826f60f00\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5d7bfd141924a5ece21eb612ad3c56612f041c1e\",\"lessThan\":\"bb4a5b3c91af3c8d705bb2e9f6f8069a70db26fc\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5d7bfd141924a5ece21eb612ad3c56612f041c1e\",\"lessThan\":\"3af0bc1bd9039e2e50abf3e2d7fee411f38bce4e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5d7bfd141924a5ece21eb612ad3c56612f041c1e\",\"lessThan\":\"2821e85c058f81c9948a2fb1a634f7b47457d51c\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"include/net/fib_rules.h\",\"net/core/fib_rules.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"4.12\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"4.12\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.261\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.212\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.178\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.145\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.97\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.40\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.5\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/0f929b59f4cd0e05bb1ecefe12b77e85911d4be2\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/1fbc6c6efe78f4454a51afa0587efb6826f60f00\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/2821e85c058f81c9948a2fb1a634f7b47457d51c\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/2dfdc210d240bd48bb2ea746430b02b5571b6db9\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/3af0bc1bd9039e2e50abf3e2d7fee411f38bce4e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/4b7ae30c81c2ee10a644749a3704a5c797ccc308\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/a7ef30753353ba6a95d693b1863a0214222a199a\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/bb4a5b3c91af3c8d705bb2e9f6f8069a70db26fc\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-20T15:19:09+00:00",
      "cve": "CVE-2026-74288",
      "id": "CVE-2026-74288",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "260",
      "product_status:known_not_affected": "14",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: net: fib_rules: Don\u0027t dump dying fib_rule in fib_rules_dump()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74288.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.