{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2023-52564",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2023-52564",
    "idYear": 2023,
    "status": "PUBLISHED",
    "publishedAt": "2024-03-02T21:59:36.867Z",
    "updatedAt": "2026-05-23T15:26:08.197Z",
    "importedAt": "2026-10-24T01:57:03.413Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "Revert \"tty: n_gsm: fix UAF in gsm_cleanup_mux\"",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nRevert \"tty: n_gsm: fix UAF in gsm_cleanup_mux\"\n\nThis reverts commit 9b9c8195f3f0d74a826077fc1c01b9ee74907239.\n\nThe commit above is reverted as it did not solve the original issue.\n\ngsm_cleanup_mux() tries to free up the virtual ttys by calling\ngsm_dlci_release() for each available DLCI. There, dlci_put() is called to\ndecrease the reference counter for the DLCI via tty_port_put() which\nfinally calls gsm_dlci_free(). This already clears the pointer which is\nbeing checked in gsm_cleanup_mux() before calling gsm_dlci_release().\nTherefore, it is not necessary to clear this pointer in gsm_cleanup_mux()\nas done in the reverted commit. The commit introduces a null pointer\ndereference:\n <TASK>\n ? __die+0x1f/0x70\n ? page_fault_oops+0x156/0x420\n ? search_exception_tables+0x37/0x50\n ? fixup_exception+0x21/0x310\n ? exc_page_fault+0x69/0x150\n ? asm_exc_page_fault+0x26/0x30\n ? tty_port_put+0x19/0xa0\n gsmtty_cleanup+0x29/0x80 [n_gsm]\n release_one_tty+0x37/0xe0\n process_one_work+0x1e6/0x3e0\n worker_thread+0x4c/0x3d0\n ? __pfx_worker_thread+0x10/0x10\n kthread+0xe1/0x110\n ? __pfx_kthread+0x10/0x10\n ret_from_fork+0x2f/0x50\n ? __pfx_kthread+0x10/0x10\n ret_from_fork_asm+0x1b/0x30\n </TASK>\n\nThe actual issue is that nothing guards dlci_put() from being called\nmultiple times while the tty driver was triggered but did not yet finished\ncalling gsm_dlci_free().",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "8fc0eabaa73bbd9bd705577071564616da5c8c61",
              "status": "affected",
              "versionType": "git",
              "lessThan": "6d5c8862932d31a810b6545f7d69ecc124402c6e"
            },
            {
              "version": "5138c228311a863c3cf937b94a3ab4c87f1f70c4",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a48d2bcd23f2c98d575bc2f9b7a3fbd16aeea9eb"
            },
            {
              "version": "9615ca54bc138e35353a001e8b5d4824dce72188",
              "status": "affected",
              "versionType": "git",
              "lessThan": "c61d0b87a7028c2c10faffc524d748334c7b9827"
            },
            {
              "version": "9b9c8195f3f0d74a826077fc1c01b9ee74907239",
              "status": "affected",
              "versionType": "git",
              "lessThan": "2bff660e0ff349dee84dc4f6f6d10da4497f5b28"
            },
            {
              "version": "9b9c8195f3f0d74a826077fc1c01b9ee74907239",
              "status": "affected",
              "versionType": "git",
              "lessThan": "29346e217b8ab8a52889b88f00b268278d6b7668"
            },
            {
              "version": "74a8d6f50cc90ed0061997db51dfa81a62b0f835",
              "status": "affected",
              "versionType": "git"
            },
            {
              "version": "5.10.190",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "5.10.198"
            },
            {
              "version": "5.15.124",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "5.15.134"
            },
            {
              "version": "6.1.43",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "6.1.56"
            },
            {
              "version": "6.4.8",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "6.5"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "6.5",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "6.5"
            },
            {
              "version": "5.10.198",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.134",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.56",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.5.6",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.5.*"
            },
            {
              "version": "6.6",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}