Vulnerability-Lookup

GHSA-VFQP-R766-G759

Vulnerability from github – Published: 2026-04-30 21:30 – Updated: 2026-04-30 21:30

Details

Notepad++ 8.9.3 contains a format string injection vulnerability in the Find Results panel handler that allows attackers to cause denial of service and information disclosure by crafting a malicious nativeLang.xml language pack file. Attackers can distribute a poisoned language pack through community channels that triggers format string interpretation when a user performs search operations, leading to access violations and potential leakage of stack or register contents.

Severity

4.4 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L

4.6 (Medium)


                  
                    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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-6539"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-134"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-30T21:16:33Z",
    "severity": "MODERATE"
  },
  "details": "Notepad++ 8.9.3 contains a format string injection vulnerability in the Find Results panel handler that allows attackers to cause denial of service and information disclosure by crafting a malicious nativeLang.xml language pack file. Attackers can distribute a poisoned language pack through community channels that triggers format string interpretation when a user performs search operations, leading to access violations and potential leakage of stack or register contents.",
  "id": "GHSA-vfqp-r766-g759",
  "modified": "2026-04-30T21:30:39Z",
  "published": "2026-04-30T21:30:39Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6539"
    },
    {
      "type": "WEB",
      "url": "https://notepad-plus-plus.org/news/v894-released"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/notepad-format-string-injection-via-nativelang-xml"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L",
      "type": "CVSS_V3"
    },
    {
      "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/E:X/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:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-6539 (GCVE-0-2026-6539)

Vulnerability from cvelistv5 – Published: 2026-04-30 20:31 – Updated: 2026-05-01 14:21

Title

Notepad++ 8.9.3 Format String Injection via nativeLang.xml

Summary

Severity

4.6 (Medium)


                        
                          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

4.4 (Medium)


                        
                          CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-134 - Use of Externally Controlled Format String

Assigner

VulnCheck

References

2 references

URL	Tags
https://notepad-plus-plus.org/news/v894-released/	patch
https://www.vulncheck.com/advisories/notepad-form…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
Notepad++	Notepad++	Affected: 0 , < 8.9.4 (semver)

Credits

Hazley Samsudin

Show details on NVD website

JSON

To clipboard

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  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-6539",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-01T14:21:36.067358Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-01T14:21:46.872Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
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          "defaultStatus": "unaffected",
          "platforms": [
            "Windows"
          ],
          "product": "Notepad++",
          "vendor": "Notepad++",
          "versions": [
            {
              "lessThan": "8.9.4",
              "status": "affected",
              "version": "0",
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            }
          ]
        }
      ],
      "credits": [
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          "lang": "en",
          "type": "other",
          "value": "Hazley Samsudin"
        }
      ],
      "descriptions": [
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          "lang": "en",
          "supportingMedia": [
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              "base64": false,
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            }
          ],
          "value": "Notepad++ 8.9.3 contains a format string injection vulnerability in the Find Results panel handler that allows attackers to cause denial of service and information disclosure by crafting a malicious nativeLang.xml language pack file. Attackers can distribute a poisoned language pack through community channels that triggers format string interpretation when a user performs search operations, leading to access violations and potential leakage of stack or register contents."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
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            "attackVector": "LOCAL",
            "baseScore": 4.6,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
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            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "ACTIVE",
            "valueDensity": "NOT_DEFINED",
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            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "LOW",
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            "vulnerabilityResponseEffort": "NOT_DEFINED"
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            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
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          "scenarios": [
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      "providerMetadata": {
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      },
      "references": [
        {
          "tags": [
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          ],
          "url": "https://notepad-plus-plus.org/news/v894-released/"
        },
        {
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/notepad-format-string-injection-via-nativelang-xml"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
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    "dateReserved": "2026-04-17T17:20:47.595Z",
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    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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-VFQP-R766-G759

CVE-2026-6539 (GCVE-0-2026-6539)

Tags

Sightings

Nomenclature