{
    "id": "CVE-2021-36159",
    "published": "2021-08-03 14:15:08",
    "last_modified": "2026-06-17 03:58:26",
    "cvss_score": "9.1",
    "cvss_severity": "CRITICAL",
    "cvss_version": "3.1",
    "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
    "cwe": "CWE-125",
    "description": "libfetch before 2021-07-26, as used in apk-tools, xbps, and other products, mishandles numeric strings for the FTP and HTTP protocols. The FTP passive mode implementation allows an out-of-bounds read because strtol is used to parse the relevant numbers into address bytes. It does not check if the line ends prematurely. If it does, the for-loop condition checks for the '\\0' terminator one byte too late.",
    "epss_score": "0.02637",
    "epss_percentile": "0.85182",
    "kev": 0,
    "kev_due": null,
    "has_exploit": 0,
    "updated_at": "2026-10-13 18:17:28",
    "priority": {
        "rank": 3,
        "label": "In your normal cycle",
        "why": "Critical by CVSS (9.1), but no sign of active exploitation."
    },
    "products": [
        {
            "vendor": "freebsd",
            "product": "libfetch"
        }
    ],
    "kev_detail": null,
    "exploits": [],
    "refs_list": [
        "https://github.com/freebsd/freebsd-src/commits/main/lib/libfetch",
        "https://gitlab.alpinelinux.org/alpine/apk-tools/-/issues/10749",
        "https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cdev.kafka.apache.org%3E",
        "https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cusers.kafka.apache.org%3E",
        "https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cdev.kafka.apache.org%3E",
        "https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cusers.kafka.apache.org%3E",
        "https://github.com/freebsd/freebsd-src/commits/main/lib/libfetch",
        "https://gitlab.alpinelinux.org/alpine/apk-tools/-/issues/10749",
        "https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cdev.kafka.apache.org%3E",
        "https://lists.apache.org/thread.html/r61db8e7dcb56dc000a5387a88f7a473bacec5ee01b9ff3f55308aacc%40%3Cusers.kafka.apache.org%3E",
        "https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cdev.kafka.apache.org%3E",
        "https://lists.apache.org/thread.html/rbf4ce74b0d1fa9810dec50ba3ace0caeea677af7c27a97111c06ccb7%40%3Cusers.kafka.apache.org%3E"
    ]
}