CVE catalog

CVE-2026-4800

The fix for CVE-2021-23337 added validation for the…

[CVE catalog]

The fix for CVE-2021-23337 added validation for the variable option in _.template but did not apply the same validation to options.imports key names, and both paths flow into the same Function() constructor sink. When an application passes untrusted input as options.imports key names, an attacker can inject default-parameter expressions that execute arbitrary code at template compilation time. Additionally, _.template uses assignInWith to merge imports, which enumerates inherited properties via for..in, so if Object.prototype has been polluted by another vector the polluted keys are copied into the imports object and passed to Function(). The issue is fixed in 4.18.1 for lodash, lodash-es, lodash-amd, and lodash.template. As a workaround, do not pass untrusted input as key names in options.imports; use only developer-controlled, static key names.

Severity
Critical · CVSS 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published
Source
[NVD] · [CVE record]
EPSS
2.76% · Oct 27, 2026

Projects and upstream resources

Reported versions and fixes

Each observation applies to its named package, distribution, and release. Distribution backports can fix a vulnerability while retaining an older upstream version number.

Version impact has not been established. The original provider fields are retained below.

Provider details and historical evidence
Original provider fields
{
  "package_releases": [
    {
      "name": "node-lodash",
      "status": "fixed",
      "release": "sid",
      "version": "4.18.1+dfsg1-2"
    },
    {
      "name": "node-lodash",
      "status": "fixed",
      "release": "forky",
      "version": "4.18.1+dfsg1-2"
    },
    {
      "name": "node-lodash",
      "status": "fixed",
      "release": "trixie",
      "version": "4.17.21+dfsg+~cs8.31.198.20210220-9+deb13u1"
    },
    {
      "name": "node-lodash",
      "status": "vulnerable",
      "release": "bookworm",
      "version": "4.17.21+dfsg+~cs8.31.198.20210220-9"
    },
    {
      "name": "node-lodash",
      "status": "fixed",
      "release": "bookworm-security",
      "version": "4.17.21+dfsg+~cs8.31.198.20210220-9+deb12u1"
    }
  ],
  "fixed_versions": [
    {
      "bug": 1132500,
      "name": "node-lodash",
      "type": "source",
      "origin": null,
      "release": "sid",
      "urgency": "not yet assigned",
      "fixed_version": "4.18.1+dfsg-1"
    },
    {
      "bug": 1132500,
      "name": "node-lodash",
      "type": "source",
      "origin": null,
      "release": "forky",
      "urgency": "not yet assigned",
      "fixed_version": "4.18.1+dfsg-1"
    },
    {
      "bug": 1132500,
      "name": "node-lodash",
      "type": "source",
      "origin": null,
      "release": "trixie",
      "urgency": "not yet assigned",
      "fixed_version": "4.17.21+dfsg+~cs8.31.198.20210220-9+deb13u1"
    },
    {
      "bug": 1132500,
      "name": "node-lodash",
      "type": "source",
      "origin": null,
      "release": "bookworm",
      "urgency": "not yet assigned",
      "fixed_version": "4.17.21+dfsg+~cs8.31.198.20210220-9+deb12u1"
    }
  ],
  "distribution_packages": [
    {
      "name": "node-lodash",
      "ecosystem": "cpe",
      "fixed_version": "4.17.21+dfsg+~cs8.31.198.20210220-9ubuntu0.24.04.1~esm1"
    },
    {
      "name": "libjs-lodash",
      "ecosystem": "cpe",
      "fixed_version": "4.17.21+dfsg+~cs8.31.198.20210220-9ubuntu0.24.04.1~esm1"
    },
    {
      "name": "node-lodash-packages",
      "ecosystem": "cpe",
      "fixed_version": "4.17.21+dfsg+~cs8.31.198.20210220-9ubuntu0.24.04.1~esm1"
    },
    {
      "name": "node-lodash",
      "ecosystem": "cpe",
      "fixed_version": "not yet fixed"
    },
    {
      "name": "lodash",
      "ecosystem": "cpe",
      "fixed_version": "4.18.0"
    },
    {
      "name": "lodash-amd",
      "ecosystem": "cpe",
      "fixed_version": "4.18.0"
    },
    {
      "name": "lodash-es",
      "ecosystem": "cpe",
      "fixed_version": "4.18.0"
    },
    {
      "name": "lodash.template",
      "ecosystem": "cpe",
      "fixed_version": "4.18.0"
    },
    {
      "name": "lodash",
      "ranges": [
        {
          "fixed": "4.18.0",
          "introduced": "4.0.0",
          "last_affected": "",
          "start_excluding": ""
        }
      ],
      "ecosystem": "cpe",
      "fixed_version": "4.18.0",
      "provider_record_id": "NVD-CVE-2026-4800"
    },
    {
      "name": "lodash-amd",
      "ranges": [
        {
          "fixed": "4.18.0",
          "introduced": "4.0.0",
          "last_affected": "",
          "start_excluding": ""
        }
      ],
      "ecosystem": "cpe",
      "fixed_version": "4.18.0",
      "provider_record_id": "NVD-CVE-2026-4800"
    },
    {
      "name": "lodash-es",
      "ranges": [
        {
          "fixed": "4.18.0",
          "introduced": "4.0.0",
          "last_affected": "",
          "start_excluding": ""
        }
      ],
      "ecosystem": "cpe",
      "fixed_version": "4.18.0",
      "provider_record_id": "NVD-CVE-2026-4800"
    },
    {
      "name": "lodash.template",
      "ranges": [
        {
          "fixed": "4.18.0",
          "introduced": "4.0.0",
          "last_affected": "",
          "start_excluding": ""
        }
      ],
      "ecosystem": "cpe",
      "fixed_version": "4.18.0",
      "provider_record_id": "NVD-CVE-2026-4800"
    },
    {
      "name": "lodash",
      "ranges": [
        {
          "type": "SEMVER",
          "events": [
            {
              "introduced": "4.0.0"
            },
            {
              "fixed": "4.18.0"
            }
          ]
        }
      ],
      "ecosystem": "npm",
      "fixed_version": "4.18.0",
      "provider_record_id": "GHSA-R5FR-RJXR-66JC"
    },
    {
      "name": "lodash-es",
      "ranges": [
        {
          "type": "SEMVER",
          "events": [
            {
              "introduced": "4.0.0"
            },
            {
              "fixed": "4.18.0"
            }
          ]
        }
      ],
      "ecosystem": "npm",
      "fixed_version": "4.18.0",
      "provider_record_id": "GHSA-R5FR-RJXR-66JC"
    },
    {
      "name": "lodash-amd",
      "ranges": [
        {
          "type": "SEMVER",
          "events": [
            {
              "introduced": "4.0.0"
            },
            {
              "fixed": "4.18.0"
            }
          ]
        }
      ],
      "ecosystem": "npm",
      "fixed_version": "4.18.0",
      "provider_record_id": "GHSA-R5FR-RJXR-66JC"
    },
    {
      "name": "lodash.template",
      "ranges": [
        {
          "type": "SEMVER",
          "events": [
            {
              "introduced": "4.0.0"
            },
            {
              "fixed": "4.18.0"
            }
          ]
        }
      ],
      "ecosystem": "npm",
      "fixed_version": "4.18.0",
      "provider_record_id": "GHSA-R5FR-RJXR-66JC"
    },
    {
      "name": "node-lodash",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            },
            {
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            }
          ]
        }
      ],
      "release": "pro",
      "versions": [
        "4.17.21+dfsg+~cs8.31.198.20210220-9",
        "4.17.23+dfsg-1"
      ],
      "ecosystem": "deb",
      "fixed_version": "4.17.23+dfsg-1ubuntu0.1~esm1",
      "provider_record_id": "UBUNTU-CVE-2026-4800"
    },
    {
      "name": "node-lodash",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            },
            {
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            }
          ]
        }
      ],
      "release": "25.10",
      "versions": [
        "4.17.21+dfsg+~cs8.31.198.20210220-9"
      ],
      "ecosystem": "deb",
      "fixed_version": "4.17.21+dfsg+~cs8.31.198.20210220-9ubuntu0.25.10.1",
      "provider_record_id": "UBUNTU-CVE-2026-4800"
    },
    {
      "name": "node-lodash",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "26.10",
      "versions": [
        "4.17.23+dfsg-1",
        "4.18.1+dfsg-3",
        "4.18.1+dfsg1-1",
        "4.18.1+dfsg1-2"
      ],
      "ecosystem": "deb",
      "fixed_version": "",
      "provider_record_id": "UBUNTU-CVE-2026-4800"
    }
  ]
}

[Debian bug #1132500]

OpenFactory catalog packages

Matching against OpenFactory catalog package versions is in progress.

[Debian 12 (Bookworm)]

  • [libjs-lodash]Unknown

    Source package: [node-lodash]

    Details (2)

    • 4.17.21+dfsg+~cs8.31.198.20210220-9 · all · bookworm

      Affected · Fixed: 4.17.21+dfsg+~cs8.31.198.20210220-9+deb12u1

      nvd · node-lodash · debian · bookworm

    • 4.17.21+dfsg+~cs8.31.198.20210220-9 · all · bookworm

      Affected · Fixed: 4.17.21+dfsg+~cs8.31.198.20210220-9+deb12u1

      nvd · node-lodash · debian · bookworm

  • [node-lodash]Unknown
    Details (2)

    • 4.17.21+dfsg+~cs8.31.198.20210220-9 · all · bookworm

      Affected · Fixed: 4.17.21+dfsg+~cs8.31.198.20210220-9+deb12u1

      nvd · node-lodash · debian · bookworm

    • 4.17.21+dfsg+~cs8.31.198.20210220-9 · all · bookworm

      Affected · Fixed: 4.17.21+dfsg+~cs8.31.198.20210220-9+deb12u1

      nvd · node-lodash · debian · bookworm

  • [node-lodash-packages]Unknown

    Source package: [node-lodash]

    Details (2)

    • 4.17.21+dfsg+~cs8.31.198.20210220-9 · all · bookworm

      Affected · Fixed: 4.17.21+dfsg+~cs8.31.198.20210220-9+deb12u1

      nvd · node-lodash · debian · bookworm

    • 4.17.21+dfsg+~cs8.31.198.20210220-9 · all · bookworm

      Affected · Fixed: 4.17.21+dfsg+~cs8.31.198.20210220-9+deb12u1

      nvd · node-lodash · debian · bookworm

Observed:

References

[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX] · [Ubuntu Security Notices (USN)]