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CVE-2026-63809 (GCVE-0-2026-63809)

Vulnerability from cvelistv5 – Published: 2026-07-19 12:02 – Updated: 2026-08-17 04:51
VLAI
Title
bpf: use kvfree() for replaced sysctl write buffer
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: use kvfree() for replaced sysctl write buffer proc_sys_call_handler() allocates its temporary sysctl buffer with kvzalloc() and passes it to __cgroup_bpf_run_filter_sysctl(). Since kvzalloc() may fall back to vmalloc() for large allocations, freeing that buffer with kfree() is wrong and can corrupt memory. Use kvfree() to safely handle both kmalloc and kvzalloc()/vmalloc allocations. The bug was first flagged by an experimental analysis tool we are developing for kernel memory-management bugs while analyzing v6.13-rc1. The tool is still under development and is not yet publicly available. Manual inspection confirms that the bug is still present in v7.1-rc5. Reproduced the bug based on v7.1-rc4 in a QEMU x86_64 guest booted with KASAN and CONFIG_FAILSLAB enabled. To exercise the replacement path, the test tree also included the accompanying fix for the stale ret == 1 check in __cgroup_bpf_run_filter_sysctl(). The reproducer confines failslab injections to the proc_sys_call_handler() range, uses stacktrace-depth=32, and injects fail-nth=1 while writing 8191 bytes to /proc/sys/kernel/domainname from a task in the target cgroup. Under that setup, fail-nth=1 triggered the fault: BUG: unable to handle page fault for address: ffffeb0200024d48 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 SMP KASAN NOPTI CPU: 2 UID: 0 PID: 209 Comm: repro_proc_sys_ Not tainted 7.1.0-rc4-00686-g97625979a5d4 PREEMPT(lazy) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 RIP: 0010:kfree+0x6e/0x510 ... Call Trace: <TASK> ? __cgroup_bpf_run_filter_sysctl+0x626/0xc30 __cgroup_bpf_run_filter_sysctl+0x74d/0xc30 ? __pfx___cgroup_bpf_run_filter_sysctl+0x10/0x10 ? srso_return_thunk+0x5/0x5f ? __kvmalloc_node_noprof+0x345/0x870 ? proc_sys_call_handler+0x250/0x480 ? srso_return_thunk+0x5/0x5f proc_sys_call_handler+0x3a2/0x480 ? __pfx_proc_sys_call_handler+0x10/0x10 ? srso_return_thunk+0x5/0x5f ? selinux_file_permission+0x39f/0x500 ? srso_return_thunk+0x5/0x5f ? lock_is_held_type+0x9e/0x120 vfs_write+0x98e/0x1000 ... </TASK> With this fix applied on top of the same test setup, rerunning the reproducer with fail-nth=1 yields no corresponding Oops reports.
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: b7925acd82926ebbf94a0f0783a3961f4e558856 , < d0a81ed5ff5d0f9c3f63a4f9e5a4642c363ecd3e (git)
Affected: 4508943794efdd94171549c0bd52810e2f4ad9fe , < 77355ef7a9f6b0d2bdf65be3b37f2c1f365e20d2 (git)
Affected: 4508943794efdd94171549c0bd52810e2f4ad9fe , < e1d1e203a6000804c5d3b8a4aa4e52303c0c7ab2 (git)
Affected: 4508943794efdd94171549c0bd52810e2f4ad9fe , < 81fc9a13acae99966232f0e055eb2e445263b89a (git)
Affected: 4508943794efdd94171549c0bd52810e2f4ad9fe , < 838fe9c28121777c59a9406710a68fcf77bb8017 (git)
Affected: 4508943794efdd94171549c0bd52810e2f4ad9fe , < 65bd0c0afb0e1bf3287458e342429b069624f7d4 (git)
Affected: 4508943794efdd94171549c0bd52810e2f4ad9fe , < 70df4de46577fab5e25418f014583155a147c902 (git)
Affected: 4508943794efdd94171549c0bd52810e2f4ad9fe , < 4c21b5927d4364bfe7365f2700da5fea0ed0d004 (git)
Affected: 66258ab303588936ee1ee0794d9a271be24f73cb (git)
Affected: 5.10.20 , < 5.10.260 (semver)
Affected: 5.11.3 , < 5.12 (semver)
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Linux Linux Affected: 5.12
Unaffected: 0 , < 5.12 (semver)
Unaffected: 5.10.260 , ≤ 5.10.* (semver)
Unaffected: 5.15.211 , ≤ 5.15.* (semver)
Unaffected: 6.1.177 , ≤ 6.1.* (semver)
Unaffected: 6.6.144 , ≤ 6.6.* (semver)
Unaffected: 6.12.95 , ≤ 6.12.* (semver)
Unaffected: 6.18.38 , ≤ 6.18.* (semver)
Unaffected: 7.1.3 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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{
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: use kvfree() for replaced sysctl write buffer\n\nproc_sys_call_handler() allocates its temporary sysctl buffer with\nkvzalloc() and passes it to __cgroup_bpf_run_filter_sysctl(). Since\nkvzalloc() may fall back to vmalloc() for large allocations, freeing\nthat buffer with kfree() is wrong and can corrupt memory.\n\nUse kvfree() to safely handle both kmalloc and kvzalloc()/vmalloc\nallocations.\n\nThe bug was first flagged by an experimental analysis tool we are\ndeveloping for kernel memory-management bugs while analyzing\nv6.13-rc1. The tool is still under development and is not yet publicly\navailable. Manual inspection confirms that the bug is still\npresent in v7.1-rc5.\n\nReproduced the bug based on v7.1-rc4 in a QEMU x86_64 guest booted with\nKASAN and CONFIG_FAILSLAB enabled. To exercise the replacement path, the\ntest tree also included the accompanying fix for the stale ret == 1\ncheck in __cgroup_bpf_run_filter_sysctl(). The reproducer confines\nfailslab injections to the proc_sys_call_handler() range, uses\nstacktrace-depth=32, and injects fail-nth=1 while writing 8191 bytes to\n/proc/sys/kernel/domainname from a task in the target cgroup. Under\nthat setup, fail-nth=1 triggered the fault:\n\n  BUG: unable to handle page fault for address: ffffeb0200024d48\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 0 P4D 0\n  Oops: Oops: 0000  SMP KASAN NOPTI\n  CPU: 2 UID: 0 PID: 209 Comm: repro_proc_sys_ Not tainted 7.1.0-rc4-00686-g97625979a5d4  PREEMPT(lazy)\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014\n  RIP: 0010:kfree+0x6e/0x510\n  ...\n  Call Trace:\n   \u003cTASK\u003e\n   ? __cgroup_bpf_run_filter_sysctl+0x626/0xc30\n   __cgroup_bpf_run_filter_sysctl+0x74d/0xc30\n   ? __pfx___cgroup_bpf_run_filter_sysctl+0x10/0x10\n   ? srso_return_thunk+0x5/0x5f\n   ? __kvmalloc_node_noprof+0x345/0x870\n   ? proc_sys_call_handler+0x250/0x480\n   ? srso_return_thunk+0x5/0x5f\n   proc_sys_call_handler+0x3a2/0x480\n   ? __pfx_proc_sys_call_handler+0x10/0x10\n   ? srso_return_thunk+0x5/0x5f\n   ? selinux_file_permission+0x39f/0x500\n   ? srso_return_thunk+0x5/0x5f\n   ? lock_is_held_type+0x9e/0x120\n   vfs_write+0x98e/0x1000\n   ...\n   \u003c/TASK\u003e\n\nWith this fix applied on top of the same test setup, rerunning the\nreproducer with fail-nth=1 yields no corresponding Oops reports."
        }
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            "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 via a local write() to /proc/sys/* through proc_sys_call_handler() \u2192 BPF_CGROUP_RUN_PROG_SYSCTL() \u2192 __cgroup_bpf_run_filter_sysctl(); there is no network, adjacent-radio, or physical-device entry point.\nAC:L - An attacker controls all prerequisites: they can mount/join a cgroup, load and attach a cgroup/sysctl BPF program that calls bpf_sysctl_set_new_value(), issue a \u003ePAGE_SIZE sysctl write, and induce kmalloc failure (e.g., memory pressure) so kvzalloc() falls back to vmalloc and the wrong kfree() path is taken.\nPR:L - In a user+network namespace (unshare -Urn), CAP_NET_ADMIN grants write access to /proc/sys/net/* sysctls, and CAP_BPF plus CAP_NET_ADMIN suffice to load/attach BPF_PROG_TYPE_CGROUP_SYSCTL; cgroup management is available with namespace CAP_SYS_ADMIN, without init-namespace root.\nUI:N - Exploitation is fully attacker-driven through syscalls (write, bpf) and requires no victim interaction.\nS:U - Impact is kernel memory corruption and potential privilege escalation within the same kernel/host security boundary, not a cross-boundary escape such as VM or IOMMU bypass.\nC:H - Calling kfree() on a vmalloc-backed kvzalloc() buffer corrupts slab allocator metadata and can be leveraged for arbitrary kernel memory disclosure, not merely a bounded leak.\nI:H - Invalid kfree() of vmalloc memory is a heap corruption primitive that can corrupt slab freelists and be developed into arbitrary kernel writes or code execution.\nA:H - The reproducer triggers an immediate kernel oops/page fault in kfree(), and the underlying allocator corruption can also cause panics, hangs, or repeated crashes."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T04:51:15.528Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/d0a81ed5ff5d0f9c3f63a4f9e5a4642c363ecd3e"
        },
        {
          "url": "https://git.kernel.org/stable/c/77355ef7a9f6b0d2bdf65be3b37f2c1f365e20d2"
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          "url": "https://git.kernel.org/stable/c/e1d1e203a6000804c5d3b8a4aa4e52303c0c7ab2"
        },
        {
          "url": "https://git.kernel.org/stable/c/81fc9a13acae99966232f0e055eb2e445263b89a"
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          "url": "https://git.kernel.org/stable/c/838fe9c28121777c59a9406710a68fcf77bb8017"
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          "url": "https://git.kernel.org/stable/c/65bd0c0afb0e1bf3287458e342429b069624f7d4"
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        {
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        },
        {
          "url": "https://git.kernel.org/stable/c/4c21b5927d4364bfe7365f2700da5fea0ed0d004"
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      ],
      "title": "bpf: use kvfree() for replaced sysctl write buffer",
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    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-63809",
    "datePublished": "2026-07-19T12:02:11.905Z",
    "dateReserved": "2026-07-19T07:54:57.013Z",
    "dateUpdated": "2026-08-17T04:51:15.528Z",
    "state": "PUBLISHED"
  },
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  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-63809",
      "date": "2026-09-16",
      "epss": "0.00154",
      "percentile": "0.0491"
    },
    "microsoft_vex": {
      "current_release_date": "2026-08-14T18:24:35.000Z",
      "cve": "CVE-2026-63809",
      "id": "msrc_CVE-2026-63809",
      "initial_release_date": "2026-07-20T01:04:44.000Z",
      "product_status:fixed": "1",
      "product_status:known_affected": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "bpf: use kvfree() for replaced sysctl write buffer",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-63809.json",
      "version": "6"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-63809\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-07-19T12:16:53.757\",\"lastModified\":\"2026-08-17T05:17:17.913\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nbpf: use kvfree() for replaced sysctl write buffer\\n\\nproc_sys_call_handler() allocates its temporary sysctl buffer with\\nkvzalloc() and passes it to __cgroup_bpf_run_filter_sysctl(). Since\\nkvzalloc() may fall back to vmalloc() for large allocations, freeing\\nthat buffer with kfree() is wrong and can corrupt memory.\\n\\nUse kvfree() to safely handle both kmalloc and kvzalloc()/vmalloc\\nallocations.\\n\\nThe bug was first flagged by an experimental analysis tool we are\\ndeveloping for kernel memory-management bugs while analyzing\\nv6.13-rc1. The tool is still under development and is not yet publicly\\navailable. Manual inspection confirms that the bug is still\\npresent in v7.1-rc5.\\n\\nReproduced the bug based on v7.1-rc4 in a QEMU x86_64 guest booted with\\nKASAN and CONFIG_FAILSLAB enabled. To exercise the replacement path, the\\ntest tree also included the accompanying fix for the stale ret == 1\\ncheck in __cgroup_bpf_run_filter_sysctl(). The reproducer confines\\nfailslab injections to the proc_sys_call_handler() range, uses\\nstacktrace-depth=32, and injects fail-nth=1 while writing 8191 bytes to\\n/proc/sys/kernel/domainname from a task in the target cgroup. Under\\nthat setup, fail-nth=1 triggered the fault:\\n\\n  BUG: unable to handle page fault for address: ffffeb0200024d48\\n  #PF: supervisor read access in kernel mode\\n  #PF: error_code(0x0000) - not-present page\\n  PGD 0 P4D 0\\n  Oops: Oops: 0000  SMP KASAN NOPTI\\n  CPU: 2 UID: 0 PID: 209 Comm: repro_proc_sys_ Not tainted 7.1.0-rc4-00686-g97625979a5d4  PREEMPT(lazy)\\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014\\n  RIP: 0010:kfree+0x6e/0x510\\n  ...\\n  Call Trace:\\n   \u003cTASK\u003e\\n   ? __cgroup_bpf_run_filter_sysctl+0x626/0xc30\\n   __cgroup_bpf_run_filter_sysctl+0x74d/0xc30\\n   ? __pfx___cgroup_bpf_run_filter_sysctl+0x10/0x10\\n   ? srso_return_thunk+0x5/0x5f\\n   ? __kvmalloc_node_noprof+0x345/0x870\\n   ? proc_sys_call_handler+0x250/0x480\\n   ? srso_return_thunk+0x5/0x5f\\n   proc_sys_call_handler+0x3a2/0x480\\n   ? __pfx_proc_sys_call_handler+0x10/0x10\\n   ? srso_return_thunk+0x5/0x5f\\n   ? selinux_file_permission+0x39f/0x500\\n   ? srso_return_thunk+0x5/0x5f\\n   ? lock_is_held_type+0x9e/0x120\\n   vfs_write+0x98e/0x1000\\n   ...\\n   \u003c/TASK\u003e\\n\\nWith this fix applied on top of the same test setup, rerunning the\\nreproducer with fail-nth=1 yields no corresponding Oops reports.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"kernel/bpf/cgroup.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"b7925acd82926ebbf94a0f0783a3961f4e558856\",\"lessThan\":\"d0a81ed5ff5d0f9c3f63a4f9e5a4642c363ecd3e\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"4508943794efdd94171549c0bd52810e2f4ad9fe\",\"lessThan\":\"77355ef7a9f6b0d2bdf65be3b37f2c1f365e20d2\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"4508943794efdd94171549c0bd52810e2f4ad9fe\",\"lessThan\":\"e1d1e203a6000804c5d3b8a4aa4e52303c0c7ab2\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"4508943794efdd94171549c0bd52810e2f4ad9fe\",\"lessThan\":\"81fc9a13acae99966232f0e055eb2e445263b89a\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"4508943794efdd94171549c0bd52810e2f4ad9fe\",\"lessThan\":\"838fe9c28121777c59a9406710a68fcf77bb8017\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"4508943794efdd94171549c0bd52810e2f4ad9fe\",\"lessThan\":\"65bd0c0afb0e1bf3287458e342429b069624f7d4\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"4508943794efdd94171549c0bd52810e2f4ad9fe\",\"lessThan\":\"70df4de46577fab5e25418f014583155a147c902\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"4508943794efdd94171549c0bd52810e2f4ad9fe\",\"lessThan\":\"4c21b5927d4364bfe7365f2700da5fea0ed0d004\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"66258ab303588936ee1ee0794d9a271be24f73cb\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5.10.20\",\"lessThan\":\"5.10.260\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"5.11.3\",\"lessThan\":\"5.12\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"kernel/bpf/cgroup.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.12\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.12\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.260\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.211\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.177\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.144\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.95\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.38\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.3\",\"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/4c21b5927d4364bfe7365f2700da5fea0ed0d004\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/65bd0c0afb0e1bf3287458e342429b069624f7d4\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/70df4de46577fab5e25418f014583155a147c902\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/77355ef7a9f6b0d2bdf65be3b37f2c1f365e20d2\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/81fc9a13acae99966232f0e055eb2e445263b89a\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/838fe9c28121777c59a9406710a68fcf77bb8017\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/d0a81ed5ff5d0f9c3f63a4f9e5a4642c363ecd3e\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/e1d1e203a6000804c5d3b8a4aa4e52303c0c7ab2\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-20T17:11:04+00:00",
      "cve": "CVE-2026-63809",
      "id": "CVE-2026-63809",
      "initial_release_date": "2026-07-19T00:00:00+00:00",
      "product_status:known_affected": "184",
      "product_status:known_not_affected": "90",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: bpf: use kvfree() for replaced sysctl write buffer",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-63809.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-10T16:49:44Z",
      "cve": "CVE-2026-63809",
      "id": "CVE-2026-63809",
      "initial_release_date": "2026-07-19T17:34:56Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "511",
      "product_status:known_not_affected": "193",
      "product_status:recommended": "254",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-63809",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-63809.json",
      "version": "17"
    }
  }
}



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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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.