CVE-2024-56640 (GCVE-0-2024-56640)

Vulnerability from cvelistv5 – Published: 2024-12-27 15:02 – Updated: 2026-05-11 20:56
VLAI
Title
net/smc: fix LGR and link use-after-free issue
Summary
In the Linux kernel, the following vulnerability has been resolved: net/smc: fix LGR and link use-after-free issue We encountered a LGR/link use-after-free issue, which manifested as the LGR/link refcnt reaching 0 early and entering the clear process, making resource access unsafe. refcount_t: addition on 0; use-after-free. WARNING: CPU: 14 PID: 107447 at lib/refcount.c:25 refcount_warn_saturate+0x9c/0x140 Workqueue: events smc_lgr_terminate_work [smc] Call trace: refcount_warn_saturate+0x9c/0x140 __smc_lgr_terminate.part.45+0x2a8/0x370 [smc] smc_lgr_terminate_work+0x28/0x30 [smc] process_one_work+0x1b8/0x420 worker_thread+0x158/0x510 kthread+0x114/0x118 or refcount_t: underflow; use-after-free. WARNING: CPU: 6 PID: 93140 at lib/refcount.c:28 refcount_warn_saturate+0xf0/0x140 Workqueue: smc_hs_wq smc_listen_work [smc] Call trace: refcount_warn_saturate+0xf0/0x140 smcr_link_put+0x1cc/0x1d8 [smc] smc_conn_free+0x110/0x1b0 [smc] smc_conn_abort+0x50/0x60 [smc] smc_listen_find_device+0x75c/0x790 [smc] smc_listen_work+0x368/0x8a0 [smc] process_one_work+0x1b8/0x420 worker_thread+0x158/0x510 kthread+0x114/0x118 It is caused by repeated release of LGR/link refcnt. One suspect is that smc_conn_free() is called repeatedly because some smc_conn_free() from server listening path are not protected by sock lock. e.g. Calls under socklock | smc_listen_work ------------------------------------------------------- lock_sock(sk) | smc_conn_abort smc_conn_free | \- smc_conn_free \- smcr_link_put | \- smcr_link_put (duplicated) release_sock(sk) So here add sock lock protection in smc_listen_work() path, making it exclusive with other connection operations.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8 , < f502a88fdd415647a1f2dc45fac71b9c522a052b (git)
Affected: 3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8 , < 0cf598548a6c36d90681d53c6b77d52363f2f295 (git)
Affected: 3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8 , < 673d606683ac70bc074ca6676b938bff18635226 (git)
Affected: 3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8 , < 6f0ae06a234a78ae137064f2c89135ac078a00eb (git)
Affected: 3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8 , < 2c7f14ed9c19ec0f149479d1c2842ec1f9bf76d7 (git)
Create a notification for this product.
Linux Linux Affected: 4.18
Unaffected: 0 , < 4.18 (semver)
Unaffected: 5.15.174 , ≤ 5.15.* (semver)
Unaffected: 6.1.120 , ≤ 6.1.* (semver)
Unaffected: 6.6.66 , ≤ 6.6.* (semver)
Unaffected: 6.12.5 , ≤ 6.12.* (semver)
Unaffected: 6.13 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: fix LGR and link use-after-free issue\n\nWe encountered a LGR/link use-after-free issue, which manifested as\nthe LGR/link refcnt reaching 0 early and entering the clear process,\nmaking resource access unsafe.\n\n refcount_t: addition on 0; use-after-free.\n WARNING: CPU: 14 PID: 107447 at lib/refcount.c:25 refcount_warn_saturate+0x9c/0x140\n Workqueue: events smc_lgr_terminate_work [smc]\n Call trace:\n  refcount_warn_saturate+0x9c/0x140\n  __smc_lgr_terminate.part.45+0x2a8/0x370 [smc]\n  smc_lgr_terminate_work+0x28/0x30 [smc]\n  process_one_work+0x1b8/0x420\n  worker_thread+0x158/0x510\n  kthread+0x114/0x118\n\nor\n\n refcount_t: underflow; use-after-free.\n WARNING: CPU: 6 PID: 93140 at lib/refcount.c:28 refcount_warn_saturate+0xf0/0x140\n Workqueue: smc_hs_wq smc_listen_work [smc]\n Call trace:\n  refcount_warn_saturate+0xf0/0x140\n  smcr_link_put+0x1cc/0x1d8 [smc]\n  smc_conn_free+0x110/0x1b0 [smc]\n  smc_conn_abort+0x50/0x60 [smc]\n  smc_listen_find_device+0x75c/0x790 [smc]\n  smc_listen_work+0x368/0x8a0 [smc]\n  process_one_work+0x1b8/0x420\n  worker_thread+0x158/0x510\n  kthread+0x114/0x118\n\nIt is caused by repeated release of LGR/link refcnt. One suspect is that\nsmc_conn_free() is called repeatedly because some smc_conn_free() from\nserver listening path are not protected by sock lock.\n\ne.g.\n\nCalls under socklock        | smc_listen_work\n-------------------------------------------------------\nlock_sock(sk)               | smc_conn_abort\nsmc_conn_free               | \\- smc_conn_free\n\\- smcr_link_put            |    \\- smcr_link_put (duplicated)\nrelease_sock(sk)\n\nSo here add sock lock protection in smc_listen_work() path, making it\nexclusive with other connection operations."
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One suspect is that\\nsmc_conn_free() is called repeatedly because some smc_conn_free() from\\nserver listening path are not protected by sock lock.\\n\\ne.g.\\n\\nCalls under socklock        | smc_listen_work\\n-------------------------------------------------------\\nlock_sock(sk)               | smc_conn_abort\\nsmc_conn_free               | \\\\- smc_conn_free\\n\\\\- smcr_link_put            |    \\\\- smcr_link_put (duplicated)\\nrelease_sock(sk)\\n\\nSo here add sock lock protection in smc_listen_work() path, making it\\nexclusive with other connection operations.\"},{\"lang\":\"es\",\"value\":\"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net/smc: inicializar close_work antes para evitar advertencias Encontramos una advertencia que indicaba que close_work se cancel\u00f3 antes de la inicializaci\u00f3n. ADVERTENCIA: CPU: 7 PID: 111103 en kernel/workqueue.c:3047 __flush_work+0x19e/0x1b0 Workqueue: eventos smc_lgr_terminate_work [smc] RIP: 0010:__flush_work+0x19e/0x1b0 Rastreo de llamadas: ? __wake_up_common+0x7a/0x190 ? trabajo_ocupado+0x80/0x80 __cancelar_temporizador_trabajo+0xe3/0x160 smc_cerrar_cancelar_trabajo+0x1a/0x70 [smc] smc_cerrar_aborto_activo+0x207/0x360 [smc] __smc_lgr_terminate.part.38+0xc8/0x180 [smc] proceso_uno_trabajo+0x19e/0x340 subproceso_trabajador+0x30/0x370 ? proceso_uno_trabajo+0x340/0x340 kthread+0x117/0x130 ? __kthread_cancel_work+0x50/0x50 ret_from_fork+0x22/0x30 Esto se debe a que cuando se activa smc_close_cancel_work, p. ej., el controlador RDMA es rmmod y se termina el LGR, conn-\u0026gt;close_work se vac\u00eda antes de la inicializaci\u00f3n, lo que genera WARN_ON(!work-\u0026gt;func). __smc_lgr_terminate | smc_connect_{rdma|ism} ------------------------------------------------------------- | smc_conn_create | \\\\- smc_lgr_register_conn para conn en lgr-\u0026gt;conns_all | \\\\- smc_conn_kill | \\\\- smc_close_active_abort | \\\\- smc_close_cancel_work | \\\\- cancel_work_sync | \\\\- __flush_work | (close_work) | | smc_close_init | \\\\- INIT_WORK(\u0026amp;close_work) Solucione esto inicializando close_work antes de establecer la conexi\u00f3n.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"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},{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"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}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-416\"}]},{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-416\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"4.18\",\"versionEndExcluding\":\"5.15.174\",\"matchCriteriaId\":\"A8151951-069A-4828-9C8E-5430FD2D7D67\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.16\",\"versionEndExcluding\":\"6.1.120\",\"matchCriteriaId\":\"09AC6122-E2A4-40FE-9D33-268A1B2EC265\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.2\",\"versionEndExcluding\":\"6.6.66\",\"matchCriteriaId\":\"29A976AD-B9AB-4A95-9F08-7669F8847EB9\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.7\",\"versionEndExcluding\":\"6.12.5\",\"matchCriteriaId\":\"9501D045-7A94-42CA-8B03-821BE94A65B7\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"62567B3C-6CEE-46D0-BC2E-B3717FBF7D13\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/0cf598548a6c36d90681d53c6b77d52363f2f295\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/2c7f14ed9c19ec0f149479d1c2842ec1f9bf76d7\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/673d606683ac70bc074ca6676b938bff18635226\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/6f0ae06a234a78ae137064f2c89135ac078a00eb\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/f502a88fdd415647a1f2dc45fac71b9c522a052b\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\"}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CVE Program Container\", \"references\": [{\"url\": \"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html\"}], \"providerMetadata\": {\"orgId\": \"af854a3a-2127-422b-91ae-364da2661108\", \"shortName\": \"CVE\", \"dateUpdated\": \"2025-11-03T20:51:40.000Z\"}}, {\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 7.8, \"attackVector\": \"LOCAL\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"HIGH\"}}, {\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2024-56640\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2025-02-11T15:41:51.231757Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-416\", \"description\": \"CWE-416 Use After Free\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2025-02-11T15:41:52.600Z\"}}], \"cna\": {\"title\": \"net/smc: fix LGR and link use-after-free issue\", \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8\", \"lessThan\": \"f502a88fdd415647a1f2dc45fac71b9c522a052b\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8\", \"lessThan\": \"0cf598548a6c36d90681d53c6b77d52363f2f295\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8\", \"lessThan\": \"673d606683ac70bc074ca6676b938bff18635226\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8\", \"lessThan\": \"6f0ae06a234a78ae137064f2c89135ac078a00eb\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"3b2dec2603d5b06ad3af71c1164ca0b92df3d2a8\", \"lessThan\": \"2c7f14ed9c19ec0f149479d1c2842ec1f9bf76d7\", \"versionType\": \"git\"}], \"programFiles\": [\"net/smc/af_smc.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"4.18\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"4.18\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"5.15.174\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.15.*\"}, {\"status\": \"unaffected\", \"version\": \"6.1.120\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.1.*\"}, {\"status\": \"unaffected\", \"version\": \"6.6.66\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.6.*\"}, {\"status\": \"unaffected\", \"version\": \"6.12.5\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.12.*\"}, {\"status\": \"unaffected\", \"version\": \"6.13\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"net/smc/af_smc.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/f502a88fdd415647a1f2dc45fac71b9c522a052b\"}, {\"url\": \"https://git.kernel.org/stable/c/0cf598548a6c36d90681d53c6b77d52363f2f295\"}, {\"url\": \"https://git.kernel.org/stable/c/673d606683ac70bc074ca6676b938bff18635226\"}, {\"url\": \"https://git.kernel.org/stable/c/6f0ae06a234a78ae137064f2c89135ac078a00eb\"}, {\"url\": \"https://git.kernel.org/stable/c/2c7f14ed9c19ec0f149479d1c2842ec1f9bf76d7\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnet/smc: fix LGR and link use-after-free issue\\n\\nWe encountered a LGR/link use-after-free issue, which manifested as\\nthe LGR/link refcnt reaching 0 early and entering the clear process,\\nmaking resource access unsafe.\\n\\n refcount_t: addition on 0; use-after-free.\\n WARNING: CPU: 14 PID: 107447 at lib/refcount.c:25 refcount_warn_saturate+0x9c/0x140\\n Workqueue: events smc_lgr_terminate_work [smc]\\n Call trace:\\n  refcount_warn_saturate+0x9c/0x140\\n  __smc_lgr_terminate.part.45+0x2a8/0x370 [smc]\\n  smc_lgr_terminate_work+0x28/0x30 [smc]\\n  process_one_work+0x1b8/0x420\\n  worker_thread+0x158/0x510\\n  kthread+0x114/0x118\\n\\nor\\n\\n refcount_t: underflow; use-after-free.\\n WARNING: CPU: 6 PID: 93140 at lib/refcount.c:28 refcount_warn_saturate+0xf0/0x140\\n Workqueue: smc_hs_wq smc_listen_work [smc]\\n Call trace:\\n  refcount_warn_saturate+0xf0/0x140\\n  smcr_link_put+0x1cc/0x1d8 [smc]\\n  smc_conn_free+0x110/0x1b0 [smc]\\n  smc_conn_abort+0x50/0x60 [smc]\\n  smc_listen_find_device+0x75c/0x790 [smc]\\n  smc_listen_work+0x368/0x8a0 [smc]\\n  process_one_work+0x1b8/0x420\\n  worker_thread+0x158/0x510\\n  kthread+0x114/0x118\\n\\nIt is caused by repeated release of LGR/link refcnt. One suspect is that\\nsmc_conn_free() is called repeatedly because some smc_conn_free() from\\nserver listening path are not protected by sock lock.\\n\\ne.g.\\n\\nCalls under socklock        | smc_listen_work\\n-------------------------------------------------------\\nlock_sock(sk)               | smc_conn_abort\\nsmc_conn_free               | \\\\- smc_conn_free\\n\\\\- smcr_link_put            |    \\\\- smcr_link_put (duplicated)\\nrelease_sock(sk)\\n\\nSo here add sock lock protection in smc_listen_work() path, making it\\nexclusive with other connection operations.\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.15.174\", \"versionStartIncluding\": \"4.18\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.1.120\", \"versionStartIncluding\": \"4.18\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.6.66\", \"versionStartIncluding\": \"4.18\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.12.5\", \"versionStartIncluding\": \"4.18\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.13\", \"versionStartIncluding\": \"4.18\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2025-05-04T10:00:47.260Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2024-56640\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2025-11-03T20:51:40.000Z\", \"dateReserved\": \"2024-12-27T15:00:39.839Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2024-12-27T15:02:42.253Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


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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.