{
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      {
        "metrics": [
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              "content": {
                "id": "CVE-2026-53422",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-02T17:29:13.490797Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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          }
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          "dateUpdated": "2026-07-02T17:29:32.878Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
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          "cpes": [
            "cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
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          "packageName": "ssh",
          "packageURL": "pkg:otp/ssh?repository_url=https:%2F%2Fgithub.com%2Ferlang%2Fotp\u0026vcs_url=git%20https:%2F%2Fgithub.com%2Ferlang%2Fotp.git",
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          "programRoutines": [
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              "name": "ssh_sftpd:handle_op/4"
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          "repo": "https://github.com/erlang/otp",
          "vendor": "Erlang",
          "versions": [
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              "changes": [
                {
                  "at": "6.0.2",
                  "status": "unaffected"
                },
                {
                  "at": "5.5.2.2",
                  "status": "unaffected"
                },
                {
                  "at": "5.2.11.9",
                  "status": "unaffected"
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              "status": "affected",
              "version": "3.0.1",
              "versionType": "otp"
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          "packageURL": "pkg:github/erlang/otp",
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                  "status": "unaffected"
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              "status": "affected",
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                  "status": "unaffected"
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              "status": "affected",
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              "versionType": "git"
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              "value": "\u003cp\u003eThe SFTP subsystem must be configured with the \u003ctt\u003eroot\u003c/tt\u003e option in \u003ctt\u003essh_sftpd:subsystem_spec/1\u003c/tt\u003e, and the operator must rely on it to provide filesystem path isolation. The \u003ctt\u003eroot\u003c/tt\u003e option is not set by default.\u003c/p\u003e"
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          "value": "The SFTP subsystem must be configured with the root option in ssh_sftpd:subsystem_spec/1, and the operator must rely on it to provide filesystem path isolation. The root option is not set by default."
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      ],
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          "type": "finder",
          "value": "Mohamed Ali IBNAL HAJALI / Ericsson"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Micha\u0142 W\u0105sowski"
        },
        {
          "lang": "en",
          "type": "remediation reviewer",
          "value": "Jakub Witczak"
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              "value": "\u003cp\u003eObservable Response Discrepancy vulnerability in Erlang OTP \u003ctt\u003essh\u003c/tt\u003e (\u003ctt\u003essh_sftpd\u003c/tt\u003e module) allows an authenticated SFTP user to enumerate the existence of files and directories outside the configured root directory.\u003c/p\u003e\u003cp\u003eThe \u003ctt\u003eSSH_FXP_REALPATH\u003c/tt\u003e handler in \u003ctt\u003essh_sftpd\u003c/tt\u003e calls \u003ctt\u003erelate_file_name/3\u003c/tt\u003e with \u003ctt\u003eCanonicalize=false\u003c/tt\u003e, unlike every other SFTP operation handler. This allows \u003ctt\u003e..\u003c/tt\u003e components in the requested path to bypass the \u003ctt\u003eis_within_root/2\u003c/tt\u003e check without being resolved. The un-canonicalized path then enters \u003ctt\u003eresolve_symlinks/2\u003c/tt\u003e, which walks up the directory tree above the configured root and issues \u003ctt\u003eread_link()\u003c/tt\u003e syscalls on arbitrary filesystem paths.\u003c/p\u003e\u003cp\u003eAn authenticated SFTP client can exploit this by sending a \u003ctt\u003eREALPATH\u003c/tt\u003e request with a crafted traversal path. The server response differs depending on whether the target path exists on the host filesystem (\u003ctt\u003eSSH_FXP_NAME\u003c/tt\u003e when the path resolves successfully, \u003ctt\u003eSSH_FX_NO_SUCH_FILE\u003c/tt\u003e when it does not). This creates a path-existence oracle that an attacker can use to enumerate the filesystem structure outside the configured root, including the existence of sensitive files, directories, and mount points.\u003c/p\u003e\u003cp\u003eThe vulnerability leaks only the existence of paths. No file contents, credentials, or write access are obtainable through this issue alone. The information gained may assist further attacks when combined with other vulnerabilities.\u003c/p\u003e\u003cp\u003eThis vulnerability is associated with program files \u003ctt\u003elib/ssh/src/ssh_sftpd.erl\u003c/tt\u003e and program routine \u003ctt\u003essh_sftpd:handle_op/4\u003c/tt\u003e.\u003c/p\u003e\u003cp\u003eThis issue affects OTP from OTP 17.0 before OTP\u0026nbsp;29.0.3, OTP\u0026nbsp;28.5.0.3 and OTP\u0026nbsp;27.3.4.14, corresponding to \u003ctt\u003essh\u003c/tt\u003e from 3.0.1 before 6.0.2, 5.5.2.2 and 5.2.11.9.\u003c/p\u003e"
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          "value": "Observable Response Discrepancy vulnerability in Erlang OTP ssh (ssh_sftpd module) allows an authenticated SFTP user to enumerate the existence of files and directories outside the configured root directory.\n\nThe SSH_FXP_REALPATH handler in ssh_sftpd calls relate_file_name/3 with Canonicalize=false, unlike every other SFTP operation handler. This allows .. components in the requested path to bypass the is_within_root/2 check without being resolved. The un-canonicalized path then enters resolve_symlinks/2, which walks up the directory tree above the configured root and issues read_link() syscalls on arbitrary filesystem paths.\n\nAn authenticated SFTP client can exploit this by sending a REALPATH request with a crafted traversal path. The server response differs depending on whether the target path exists on the host filesystem (SSH_FXP_NAME when the path resolves successfully, SSH_FX_NO_SUCH_FILE when it does not). This creates a path-existence oracle that an attacker can use to enumerate the filesystem structure outside the configured root, including the existence of sensitive files, directories, and mount points.\n\nThe vulnerability leaks only the existence of paths. No file contents, credentials, or write access are obtainable through this issue alone. The information gained may assist further attacks when combined with other vulnerabilities.\n\nThis vulnerability is associated with program files lib/ssh/src/ssh_sftpd.erl and program routine ssh_sftpd:handle_op/4.\n\nThis issue affects OTP from OTP 17.0 before OTP\u00a029.0.3, OTP\u00a028.5.0.3 and OTP\u00a027.3.4.14, corresponding to ssh from 3.0.1 before 6.0.2, 5.5.2.2 and 5.2.11.9."
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              "lang": "en",
              "value": "CAPEC-54 Query System for Information"
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          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
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            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N",
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            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "NONE"
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              "lang": "en",
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          "url": "https://github.com/erlang/otp/security/advisories/GHSA-h9pw-h5w4-h976"
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      "source": {
        "discovery": "EXTERNAL"
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      "title": "SFTP REALPATH path-existence oracle allowing filesystem enumeration outside configured root",
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    "cveId": "CVE-2026-53422",
    "datePublished": "2026-07-02T16:06:03.802Z",
    "dateReserved": "2026-06-09T11:01:47.529Z",
    "dateUpdated": "2026-07-24T14:16:07.357Z",
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