CVE-2021-30500

Null pointer dereference was found in upx PackLinuxElf::canUnpack() in plxelf.cpp,in version UPX 4.0.0. That allow attackers to execute arbitrary code and cause a denial of service via a crafted file.

Database specific

{
    "unresolved_ranges": [
        {
            "cpes": [
                "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*"
            ],
            "source": "CPE_STRING",
            "extracted_events": [
                {
                    "introduced": "33"
                },
                {
                    "last_affected": "33"
                }
            ],
            "vendor_product": "fedoraproject:fedora"
        },
        {
            "cpes": [
                "cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*"
            ],
            "source": "CPE_STRING",
            "extracted_events": [
                {
                    "introduced": "7.0"
                },
                {
                    "last_affected": "7.0"
                }
            ],
            "vendor_product": "redhat:enterprise_linux"
        }
    ]
}

References

Affected packages

Git / github.com/upx/upx

Affected ranges

Type

GIT

Repo

https://github.com/upx/upx

Events

Introduced

69ca635c4c0ba474e9ca583dbb42e3d028c4533a

Last affected

69ca635c4c0ba474e9ca583dbb42e3d028c4533a

Fixed

90279abdfcd235172eab99651043051188938dcc

Database specific

{
    "cpe": "cpe:2.3:a:upx:upx:4.0.0:*:*:*:*:*:*:*",
    "source": [
        "CPE_STRING",
        "REFERENCES"
    ],
    "extracted_events": [
        {
            "introduced": "4.0.0"
        },
        {
            "last_affected": "4.0.0"
        }
    ]
}

Affected versions

4.*

4.0.0

v4.*

v4.0.0

Database specific

vanir_signatures_modified

"2026-07-09T00:14:02Z"

vanir_signatures

[
    {
        "signature_type": "Function",
        "target": {
            "file": "src/p_lx_elf.cpp",
            "function": "PackLinuxElf32::canUnpack"
        },
        "deprecated": false,
        "source": "https://github.com/upx/upx/commit/90279abdfcd235172eab99651043051188938dcc",
        "id": "CVE-2021-30500-1db58217",
        "signature_version": "v1",
        "digest": {
            "function_hash": "195659927832214189917620206032031836622",
            "length": 187.0
        }
    },
    {
        "signature_type": "Function",
        "target": {
            "file": "src/p_lx_elf.cpp",
            "function": "PackLinuxElf64::canUnpack"
        },
        "deprecated": false,
        "source": "https://github.com/upx/upx/commit/90279abdfcd235172eab99651043051188938dcc",
        "id": "CVE-2021-30500-a331cfa2",
        "signature_version": "v1",
        "digest": {
            "function_hash": "297660809110354721268824656352953698232",
            "length": 678.0
        }
    },
    {
        "signature_type": "Line",
        "target": {
            "file": "src/p_lx_elf.cpp"
        },
        "deprecated": false,
        "source": "https://github.com/upx/upx/commit/90279abdfcd235172eab99651043051188938dcc",
        "id": "CVE-2021-30500-e010c96c",
        "signature_version": "v1",
        "digest": {
            "line_hashes": [
                "67808947422885382892001242696481940408",
                "248774463811149992663541651901235319961",
                "86334854398016093809039749763893135532",
                "317261114776454577962241975778966464315",
                "54005563392294180897993548789785126937",
                "245740544534781845508031889732424515074",
                "272111553269849423416259819047661130422",
                "213855792622867085735299794779365703227",
                "216478141590148980457976540764247459929",
                "274930623838235982655322564949524819121",
                "47113020994492468516410760695982302936",
                "86334854398016093809039749763893135532",
                "107370910835469206454149122140010260115",
                "255830532206859043250869008652145294010",
                "74292198608600530625601120046048391471",
                "98584086108833330075633664089875600274",
                "25965964887037125459983560885222598586",
                "282492245537366763669467335669003515783"
            ],
            "threshold": 0.9
        }
    }
]

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-30500.json"