High

JavaScript::Minifier::XS versions before 0.16 for Perl leak memory on every call to minify(), allowing unbounded memory growth

Type: advisorySources: OSV

JavaScript::Minifier::XS versions before 0.16 for Perl leak memory on every call to minify(), allowing unbounded memory growth. In JsMinify (XS.xs) the cleanup frees only the NodeSet structures and never the per-token contents buffers allocated in JsSetNodeContents; JsDiscardNode unlinks nodes without freeing their contents. Each token's contents buffer is therefore leaked on every call, and the two early returns taken when the node list is empty leak the whole NodeSet. A long-lived process that minifies repeatedly, such as an asset pipeline or a server-side minifier endpoint, grows in memory without bound until it exhausts available memory and is killed, causing denial of service.

Products: Not specified
Affected versions: Not specified
Fixed versions: Not specified
CVEs: CVE-2026-56018
Confirmed fixed CVEs: Not specified
Updated in this feed: 3 Nov 2026, 08:45 UTC · Revision 1

Source evidence

JavaScript::Minifier::XS versions before 0.16 for Perl leak memory on every call to minify(), allowing unbounded memory growth

core-osv · Original source

Published 29 Jun 2026, 19:38 UTC

osv:CVE-2026-56018

Complete source record

{
  "id": "4e3e9727db334424df7c36fe3d012c14048357d2381509850146dd708fdc4c6b",
  "url": "https://osv.dev/vulnerability/CVE-2026-56018",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "JavaScript::Minifier::XS versions before 0.16 for Perl leak memory on every call to minify(), allowing unbounded memory growth",
    "summary": "JavaScript::Minifier::XS versions before 0.16 for Perl leak memory on every call to minify(), allowing unbounded memory growth. In JsMinify (XS.xs) the cleanup frees only the NodeSet structures and never the per-token contents buffers allocated in JsSetNodeContents; JsDiscardNode unlinks nodes without freeing their contents. Each token's contents buffer is therefore leaked on every call, and the two early returns taken when the node list is empty leak the whole NodeSet. A long-lived process that minifies repeatedly, such as an asset pipeline or a server-side minifier endpoint, grows in memory without bound until it exhausts available memory and is killed, causing denial of service.",
    "evidence": "osv:CVE-2026-56018",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-56018",
      "aliases": [
        "CVE-2026-56018"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/bleargh45/javascript-minifier-xs",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "84461af21b2e433d5ed65c31d7d901cfae9dc7f4"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "0.16"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "0.16"
                      }
                    ],
                    "source": "DESCRIPTION"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v0.15",
            "v0.14",
            "v0.13",
            "v0.12",
            "v0.11",
            "v0.10",
            "v0.09",
            "v0.08",
            "v0.07",
            "v0.06",
            "v0.05",
            "v0.04",
            "v0.03",
            "v0.02",
            "v0.01",
            "v0.01_05",
            "v0.01_04",
            "v0.01_03",
            "v0.01_02",
            "v0.01_01"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-56018.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:27.197195543Z",
      "provider": "osv",
      "references": [
        "https://cpan.org/modules",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56018.json",
        "https://metacpan.org/release/GTERMARS/JavaScript-Minifier-XS-0.16/changes",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-56018",
        "https://github.com/bleargh45/JavaScript-Minifier-XS/issues/10",
        "https://github.com/bleargh45/JavaScript-Minifier-XS"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-400",
          "CWE-401"
        ],
        "cna_assigner": "CPANSec",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56018.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-56018",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 493958,
  "published_at": "2026-06-29T19:38:35.316+00:00"
}