Vulnerability-Lookup

GHSA-PX8P-9VWX-VF98

Vulnerability from github – Published: 2026-07-22 09:32 – Updated: 2026-07-22 09:32

Details

fflate through 0.8.2 is vulnerable to denial of service via an infinite loop in unzipSync(). A crafted ZIP archive with a central directory entry declaring compressed_size=0xFFFFFFFF (ZIP64 sentinel) but missing the required ZIP64 extra field tag 0x0001 causes z64e() to loop indefinitely due to out-of-bounds reads returning undefined, which coerces to 0, keeping the loop condition permanently true.

Severity

6.6 (Medium)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/S:N/AU:Y/R:U/V:D/RE:M/U:Amber

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{
  "affected": [],
  "aliases": [
    "CVE-2026-45820"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-22T08:16:23Z",
    "severity": "MODERATE"
  },
  "details": "fflate through 0.8.2 is vulnerable to denial of service via an infinite loop in unzipSync(). A crafted ZIP archive with a central directory entry declaring compressed_size=0xFFFFFFFF (ZIP64 sentinel) but missing the required ZIP64 extra field tag 0x0001 causes z64e() to loop indefinitely due to out-of-bounds reads returning undefined, which coerces to 0, keeping the loop condition permanently true.",
  "id": "GHSA-px8p-9vwx-vf98",
  "modified": "2026-07-22T09:32:13Z",
  "published": "2026-07-22T09:32:13Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-45820"
    },
    {
      "type": "WEB",
      "url": "https://github.com/101arrowz/fflate/blob/f7873560ad229c22c4b23b06c6a3806ffde77569/src/index.ts#L2714"
    },
    {
      "type": "WEB",
      "url": "https://www.npmjs.com/package/fflate"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:N/AU:Y/R:U/V:D/RE:M/U:Amber",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-45820 (GCVE-0-2026-45820)

Vulnerability from cvelistv5 – Published: 2026-07-22 06:57 – Updated: 2026-07-22 12:53

Summary

Severity

6.6 (Medium)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/S:N/AU:Y/R:U/V:D/RE:M/U:Amber

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
CWE-400 - Uncontrolled Resource Consumption

Assigner

seal

References

2 references

URL	Tags
https://github.com/101arrowz/fflate/blob/f7873560…
https://www.npmjs.com/package/fflate

Impacted products

1 product

Vendor	Product	Version
101arrowz	fflate	Affected: 0.4.5 , ≤ 0.4.8 (semver) Affected: 0.5.0 , ≤ 0.5.3 (semver) Affected: 0.6.0 , ≤ 0.6.10 (semver) Affected: 0.7.0 , ≤ 0.7.4 (semver) Affected: 0.8.0 , ≤ 0.8.2 (semver)

Credits

Seal Security

Show details on NVD website

JSON

To clipboard

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  "containers": {
    "adp": [
      {
        "metrics": [
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            "other": {
              "content": {
                "id": "CVE-2026-45820",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-22T12:53:26.309456Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-22T12:53:38.246Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "platforms": [
            "Linux",
            "macOS",
            "Windows"
          ],
          "product": "fflate",
          "vendor": "101arrowz",
          "versions": [
            {
              "lessThanOrEqual": "0.4.8",
              "status": "affected",
              "version": "0.4.5",
              "versionType": "semver"
            },
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              "lessThanOrEqual": "0.5.3",
              "status": "affected",
              "version": "0.5.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "0.6.10",
              "status": "affected",
              "version": "0.6.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "0.7.4",
              "status": "affected",
              "version": "0.7.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "0.8.2",
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            "Recovery": "USER",
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          "scenarios": [
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        },
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      ],
      "source": {
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-PX8P-9VWX-VF98

CVE-2026-45820 (GCVE-0-2026-45820)

Tags

Sightings

Nomenclature