{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-90954",
        "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "state": "PUBLISHED",
        "assignerShortName": "redhat",
        "dateReserved": "2026-09-14T11:58:18.067Z",
        "datePublished": "2026-10-14T10:00:08.215Z",
        "dateUpdated": "2026-10-14T10:00:08.215Z"
    },
    "containers": {
        "cna": {
            "title": "Busybox: busybox: dpkg-deb extraction-root escape via per-ar-member deferred symlink flush",
            "metrics": [
                {
                    "other": {
                        "content": {
                            "value": "Important",
                            "namespace": "https://access.redhat.com/security/updates/classification/"
                        },
                        "type": "Red Hat severity rating"
                    }
                },
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "LOCAL",
                        "availabilityImpact": "HIGH",
                        "baseScore": 7.8,
                        "baseSeverity": "HIGH",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "REQUIRED",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
                        "version": "3.1"
                    },
                    "format": "CVSS"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "A flaw was found in BusyBox's dpkg-deb archive extraction. The ar archive handler flushes deferred symlinks after each archive member, unlike the tar, cpio, and unzip handlers which flush once after the last member. A specially crafted .deb archive with two data.tar members can exploit this ordering: the first member declares a symlink pointing to an absolute path (e.g., '/'), which is deferred as unsafe but flushed after the first member. The second member declares a regular file whose path traverses the now-live symlink, resulting in a file being written outside the intended extraction directory. This could allow an attacker to write arbitrary files to arbitrary locations when a user extracts a crafted .deb package."
                }
            ],
            "affected": [
                {
                    "vendor": "Red Hat",
                    "product": "Red Hat Hardened Images",
                    "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
                    "packageName": "busybox",
                    "defaultStatus": "affected",
                    "cpes": [
                        "cpe:/a:redhat:hummingbird:1"
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://access.redhat.com/security/cve/CVE-2026-90954",
                    "tags": [
                        "vdb-entry",
                        "x_refsource_REDHAT"
                    ]
                },
                {
                    "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2533007",
                    "name": "RHBZ#2533007",
                    "tags": [
                        "issue-tracking",
                        "x_refsource_REDHAT"
                    ]
                }
            ],
            "datePublic": "2026-10-14T08:00:00.000Z",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-59",
                            "description": "Improper Link Resolution Before File Access ('Link Following')",
                            "lang": "en",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "x_redhatCweChain": "CWE-59: Improper Link Resolution Before File Access ('Link Following')",
            "workarounds": [
                {
                    "lang": "en",
                    "value": "Do not use BusyBox dpkg-deb to extract untrusted .deb packages. Use Debian's reference dpkg-deb implementation, which treats the extraction root as a boundary and is not affected by this issue. If BusyBox dpkg-deb must be used, inspect .deb archives for multiple data.tar members before extraction (legitimate .deb packages contain exactly one data.tar member)."
                }
            ],
            "timeline": [
                {
                    "lang": "en",
                    "time": "2026-09-14T00:00:00.000Z",
                    "value": "Reported to Red Hat."
                },
                {
                    "lang": "en",
                    "time": "2026-10-14T08:00:00.000Z",
                    "value": "Made public."
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Red Hat would like to thank Shubham Raj (Causal Security) for reporting this issue."
                }
            ],
            "providerMetadata": {
                "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
                "shortName": "redhat",
                "dateUpdated": "2026-10-14T10:00:08.215Z"
            },
            "x_generator": {
                "engine": "cvelib 1.8.0"
            }
        }
    }
}