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Medium

zlib <= 1.3.1.2 untgz Global Buffer Overflow in TGZfname()

Type: advisorySources: OSV

zlib versions up to and including 1.3.1.2 include a global buffer overflow in the untgz utility located under contrib/untgz. The vulnerability is limited to the standalone demonstration utility and does not affect the core zlib compression library. The flaw occurs when a user executes the untgz command with an excessively long archive name supplied via the command line, leading to an out-of-bounds write in a fixed-size global buffer.

Products
Not specified
Affected versions
Not specified
Fixed versions
Not specified
CVEs
CVE-2026-22184
Confirmed fixed CVEs
Not specified
Updated in this feed
2 Nov 2026, 17:17 UTC · Revision 1

Source evidence

zlib <= 1.3.1.2 untgz Global Buffer Overflow in TGZfname()

core-osv · Original source

Published 7 Jan 2026, 20:25 UTC

zlib versions up to and including 1.3.1.2 include a global buffer overflow in the untgz utility located under contrib/untgz. The vulnerability is limited to the standalone demonstration utility and does not affect the core zlib compression library. The flaw occurs when a user executes the untgz command with an excessively long archive name supplied via the command line, leading to an out-of-bounds write in a fixed-size global buffer.

osv:CVE-2026-22184
Complete source record
{
  "id": "280dcfa1f4e0f37a77bde71eb3d3841303841c37001b3ba51778eda6310165fb",
  "url": "https://osv.dev/vulnerability/CVE-2026-22184",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "zlib <= 1.3.1.2 untgz Global Buffer Overflow in TGZfname()",
    "summary": "zlib versions up to and including 1.3.1.2 include a global buffer overflow in the untgz utility located under contrib/untgz. The vulnerability is limited to the standalone demonstration utility and does not affect the core zlib compression library. The flaw occurs when a user executes the untgz command with an excessively long archive name supplied via the command line, leading to an out-of-bounds write in a fixed-size global buffer.",
    "evidence": "osv:CVE-2026-22184",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-22184",
      "aliases": [
        "CVE-2026-22184"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/madler/zlib",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "570720b0c24f9686c33f35a1b3165c1f568b96be"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "1.3.1.2"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "cpe": "cpe:2.3:a:zlib:zlib:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "1.3.1.2"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.3.1.2",
            "v1.3.1",
            "v1.3",
            "v1.2.13",
            "v1.2.12",
            "v1.2.11",
            "v1.2.10",
            "v1.2.9",
            "v1.2.8",
            "v1.2.7.3",
            "v1.2.7.2",
            "v1.2.7.1",
            "v1.2.7",
            "v1.2.6.1",
            "v1.2.6",
            "v1.2.5.3",
            "v1.2.5.2",
            "v1.2.5.1",
            "v1.2.5",
            "v1.2.4.5",
            "v1.2.4.4",
            "v1.2.4.3",
            "v1.2.4.2",
            "v1.2.4.1",
            "v1.2.4",
            "v1.2.4-pre2",
            "v1.2.4-pre1",
            "v1.2.3.9",
            "v1.2.3.8",
            "v1.2.3.7",
            "v1.2.3.6",
            "v1.2.3.5",
            "v1.2.3.4",
            "v1.2.3.3",
            "v1.2.3.2",
            "v1.2.3.1",
            "v1.2.3",
            "v1.2.2.4",
            "v1.2.2.3",
            "v1.2.2.2",
            "v1.2.2.1",
            "v1.2.2",
            "v1.2.1.2",
            "v1.2.1.1",
            "v1.2.1",
            "v1.2.0.8",
            "v1.2.0.7",
            "v1.2.0.6",
            "v1.2.0.5",
            "v1.2.0.4",
            "v1.2.0.3",
            "v1.2.0.2",
            "v1.2.0.1",
            "v1.2.0",
            "v1.1.4",
            "v1.1.3",
            "v1.1.2",
            "v1.1.1",
            "v1.1.0",
            "v1.0.9",
            "v1.0.8",
            "v1.0.7",
            "v1.0.5",
            "v1.0.4",
            "v1.0.2",
            "v1.0.1",
            "v1.0-pre",
            "v0.99",
            "v0.95",
            "v0.94",
            "v0.93",
            "v0.92",
            "v0.91",
            "v0.9",
            "v0.8",
            "v0.79",
            "v0.71"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-22184.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:21.784701275Z",
      "provider": "osv",
      "references": [
        "https://cert-portal.siemens.com/productcert/html/ssa-470355.html",
        "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-22184.json",
        "https://zlib.net/",
        "https://access.redhat.com/security/cve/CVE-2026-22184",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/22xxx/CVE-2026-22184.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-22184",
        "https://www.vulncheck.com/advisories/zlib-untgz-global-buffer-overflow-in-tgzfname",
        "https://bugzilla.redhat.com/show_bug.cgi?id=2427688",
        "https://github.com/madler/zlib/issues/1142",
        "https://github.com/madler/zlib",
        "https://seclists.org/fulldisclosure/2026/Jan/3"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-787"
        ],
        "isDisputed": true,
        "cna_assigner": "VulnCheck",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/22xxx/CVE-2026-22184.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-22184",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 487643,
  "published_at": "2026-01-07T20:25:19.892+00:00"
}