Vulnerability-Lookup

CVE-2026-80255 (GCVE-0-2026-80255)

Vulnerability from cvelistv5 – Published: 2026-09-06 17:48 – Updated: 2026-09-15 06:03

Title

secure cookie attribute bypass with tab

Summary

A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of space (ascii code 32) immediately before the `Secure` attribute causes curl to store the cookie without its Secure flag. The cookie might then wrongfully be sent over plaintext HTTP on subsequent requests to the same host.

Severity

7.5 (High)


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

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-08 18:45 UTC

CWE

CWE-201 - Information Exposure Through Sent Data
CWE-201 - Insertion of Sensitive Information Into Sent Data

Assigner

curl redhat root

References

3 references

URL	Tags
https://curl.se/docs/CVE-2026-80255.json
https://curl.se/docs/CVE-2026-80255.html
https://hackerone.com/reports/3972395

Impacted products

3 products

Vendor	Product	Version	CPE status
curl	curl	Affected: 8.13.0 , < 8.14.2 (semver) Affected: 8.15.0 , < 8.16.1 (semver) Affected: 8.17.0 , < 8.20.1 (semver) Affected: 8.21.0 , < 8.22.0 (semver)	guessed
curl	curl	Affected: 1aea05a6c2699e80c75936d58569851555acd603 , < 4f6aa41a0145e930e766775dbe860883d350aa0a (git)	guessed
curl	curl	Affected: 8.21.0 Affected: 8.20.0 Affected: 8.19.0 Affected: 8.18.0 Affected: 8.17.0 Affected: 8.16.0 Affected: 8.15.0 Affected: 8.14.1 Affected: 8.14.0 Affected: 8.13.0	guessed

Credits

Stanislav Fort (Aisle Research) Daniel Stenberg

Show details on NVD website

JSON

To clipboard

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              "lang": "en",
              "value": "A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of\nspace (ascii code 32) immediately before the `Secure` attribute causes curl to\nstore the cookie without its Secure flag. The cookie might then wrongfully be\nsent over plaintext HTTP on subsequent requests to the same host."
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "cweId": "CWE-201",
                  "description": "Information Exposure Through Sent Data",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-09-15T06:03:13.400Z",
            "orgId": "2499f714-1537-4658-8207-48ae4bb9eae9",
            "shortName": "curl"
          },
          "references": [
            {
              "url": "https://curl.se/docs/CVE-2026-80255.json"
            },
            {
              "url": "https://curl.se/docs/CVE-2026-80255.html"
            },
            {
              "url": "https://hackerone.com/reports/3972395"
            }
          ],
          "title": "secure cookie attribute bypass with tab",
          "x_generator": {
            "engine": "cvelib 1.8.0"
          },
          "x_osv": {
            "affected": [
              {
                "ranges": [
                  {
                    "events": [
                      {
                        "introduced": "8.13.0"
                      },
                      {
                        "fixed": "8.14.2"
                      },
                      {
                        "introduced": "8.15.0"
                      },
                      {
                        "fixed": "8.16.1"
                      },
                      {
                        "introduced": "8.17.0"
                      },
                      {
                        "fixed": "8.20.1"
                      },
                      {
                        "introduced": "8.21.0"
                      },
                      {
                        "fixed": "8.22.0"
                      }
                    ],
                    "type": "SEMVER"
                  },
                  {
                    "events": [
                      {
                        "introduced": "1aea05a6c2699e80c75936d58569851555acd603"
                      },
                      {
                        "fixed": "4f6aa41a0145e930e766775dbe860883d350aa0a"
                      }
                    ],
                    "repo": "https://github.com/curl/curl.git",
                    "type": "GIT"
                  }
                ],
                "versions": [
                  "8.21.0",
                  "8.20.0",
                  "8.19.0",
                  "8.18.0",
                  "8.17.0",
                  "8.16.0",
                  "8.15.0",
                  "8.14.1",
                  "8.14.0",
                  "8.13.0"
                ]
              }
            ],
            "aliases": [
              "CVE-2026-80255"
            ],
            "credits": [
              {
                "name": "Stanislav Fort (Aisle Research)",
                "type": "finder"
              },
              {
                "name": "Daniel Stenberg",
                "type": "remediation developer"
              }
            ],
            "database_specific": {
              "CWE": {
                "desc": "Information Exposure Through Sent Data",
                "id": "CWE-201"
              },
              "URL": "https://curl.se/docs/CVE-2026-80255.json",
              "affects": "both",
              "issue": "https://hackerone.com/reports/3972395",
              "last_affected": "8.21.0",
              "package": "curl",
              "severity": "Low",
              "www": "https://curl.se/docs/CVE-2026-80255.html"
            },
            "details": "A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of\nspace (ascii code 32) immediately before the `Secure` attribute causes curl to\nstore the cookie without its Secure flag. The cookie might then wrongfully be\nsent over plaintext HTTP on subsequent requests to the same host.",
            "id": "CURL-CVE-2026-80255",
            "modified": "2026-09-07T10:34:51.00Z",
            "published": "2026-09-02T08:00:00.00Z",
            "schema_version": "1.5.0",
            "summary": "secure cookie attribute bypass with tab"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "2499f714-1537-4658-8207-48ae4bb9eae9",
        "assignerShortName": "curl",
        "cveId": "CVE-2026-80255",
        "datePublished": "2026-09-06T17:48:54.275Z",
        "dateReserved": "2026-08-26T06:25:58.220Z",
        "dateUpdated": "2026-09-15T06:03:13.400Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}

BELL-CVE-2026-80255 (CVE-2026-80255)

Vulnerability from osv_bellsoft – Published: 2026-09-04 06:05 – Updated: 2026-09-06 06:00 – Source website

Severity

7.5 (High)


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

References

URL

Type

https://docs.bell-sw.com/security/cves/CVE-2026-80255

ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Alpaquita:23",
        "name": "curl",
        "purl": "pkg:apk/alpaquita/curl?arch=source\u0026distro=23"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.1.0-r2"
            },
            {
              "fixed": "8.22.0-r0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Alpaquita:25",
        "name": "curl",
        "purl": "pkg:apk/alpaquita/curl?arch=source\u0026distro=25"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.14.0-r1"
            },
            {
              "fixed": "8.22.0-r0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Alpaquita:stream",
        "name": "curl",
        "purl": "pkg:apk/alpaquita/curl?arch=source\u0026distro=stream"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.1.2-r0"
            },
            {
              "fixed": "8.22.0-r0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "BellSoft Hardened Containers:stream",
        "name": "curl",
        "purl": "pkg:apk/bellsoft-hardened-containers/curl?arch=source\u0026distro=stream"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.1.2-r0"
            },
            {
              "fixed": "8.22.0-r0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "id": "BELL-CVE-2026-80255",
  "modified": "2026-09-06T06:00:39.715340Z",
  "published": "2026-09-04T06:05:07.956449Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://docs.bell-sw.com/security/cves/CVE-2026-80255"
    }
  ],
  "schema_version": "1.7.4",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-80255"
  ]
}

CERTFR-2026-AVI-1108

Vulnerability from certfr_avis - Published: 2026-09-02 - Updated: 2026-09-02

De multiples vulnérabilités ont été découvertes dans Curl. Certaines d'entre elles permettent à un attaquant de provoquer une atteinte à la confidentialité des données, une atteinte à l'intégrité des données et un contournement de la politique de sécurité.

Solutions

Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation).

Impacted products

	Vendor	Product	Description
	Curl	cURL et libcurl	Curl versions postérieures ou égales à 7.44.0 et antérieures à 8.22.0

References

Title

Publication Time

FKIE_CVE-2026-80255

Vulnerability from fkie_nvd - Published: 2026-09-06 18:17 - Updated: 2026-09-15 07:16

Severity

7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Summary

References

URL	Tags
2499f714-1537-4658-8207-48ae4bb9eae9	https://curl.se/docs/CVE-2026-80255.html	Patch, Vendor Advisory
2499f714-1537-4658-8207-48ae4bb9eae9	https://curl.se/docs/CVE-2026-80255.json	Vendor Advisory
2499f714-1537-4658-8207-48ae4bb9eae9	https://hackerone.com/reports/3972395	Exploit, Mitigation, Third Party Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0	https://hackerone.com/reports/3972395	Exploit, Mitigation, Third Party Advisory

Impacted products

	Vendor	Product	Version
	haxx	curl	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "curl",
          "vendor": "curl",
          "versions": [
            {
              "lessThan": "8.14.2",
              "status": "affected",
              "version": "8.13.0",
              "versionType": "semver"
            },
            {
              "lessThan": "8.16.1",
              "status": "affected",
              "version": "8.15.0",
              "versionType": "semver"
            },
            {
              "lessThan": "8.20.1",
              "status": "affected",
              "version": "8.17.0",
              "versionType": "semver"
            },
            {
              "lessThan": "8.22.0",
              "status": "affected",
              "version": "8.21.0",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "product": "curl",
          "repo": "https://github.com/curl/curl.git",
          "vendor": "curl",
          "versions": [
            {
              "lessThan": "4f6aa41a0145e930e766775dbe860883d350aa0a",
              "status": "affected",
              "version": "1aea05a6c2699e80c75936d58569851555acd603",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "product": "curl",
          "vendor": "curl",
          "versions": [
            {
              "status": "affected",
              "version": "8.21.0"
            },
            {
              "status": "affected",
              "version": "8.20.0"
            },
            {
              "status": "affected",
              "version": "8.19.0"
            },
            {
              "status": "affected",
              "version": "8.18.0"
            },
            {
              "status": "affected",
              "version": "8.17.0"
            },
            {
              "status": "affected",
              "version": "8.16.0"
            },
            {
              "status": "affected",
              "version": "8.15.0"
            },
            {
              "status": "affected",
              "version": "8.14.1"
            },
            {
              "status": "affected",
              "version": "8.14.0"
            },
            {
              "status": "affected",
              "version": "8.13.0"
            }
          ]
        }
      ],
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "99A8196C-041E-486F-80D8-40CFD4810C11",
              "versionEndExcluding": "8.22.0",
              "versionStartIncluding": "8.13.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of\nspace (ascii code 32) immediately before the `Secure` attribute causes curl to\nstore the cookie without its Secure flag. The cookie might then wrongfully be\nsent over plaintext HTTP on subsequent requests to the same host."
    }
  ],
  "id": "CVE-2026-80255",
  "lastModified": "2026-09-15T07:16:30.770",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-80255",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-08T18:45:09.883106Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-06T18:17:22.623",
  "references": [
    {
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://curl.se/docs/CVE-2026-80255.html"
    },
    {
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://curl.se/docs/CVE-2026-80255.json"
    },
    {
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9",
      "tags": [
        "Exploit",
        "Mitigation",
        "Third Party Advisory"
      ],
      "url": "https://hackerone.com/reports/3972395"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Mitigation",
        "Third Party Advisory"
      ],
      "url": "https://hackerone.com/reports/3972395"
    }
  ],
  "sourceIdentifier": "2499f714-1537-4658-8207-48ae4bb9eae9",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-201"
        }
      ],
      "source": "2499f714-1537-4658-8207-48ae4bb9eae9",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-201"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}

GHSA-VMMM-3JQX-JGX8

Vulnerability from github – Published: 2026-09-06 18:34 – Updated: 2026-09-08 21:33

Details

A Set-Cookie: header using tab (horizontal tab, ASCII code 9) instead of space (ascii code 32) immediately before the Secure attribute causes curl to store the cookie without its Secure flag. The cookie might then wrongfully be sent over plaintext HTTP on subsequent requests to the same host.

Severity

7.5 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-80255"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-201"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-06T18:17:22Z",
    "severity": "HIGH"
  },
  "details": "A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of\nspace (ascii code 32) immediately before the `Secure` attribute causes curl to\nstore the cookie without its Secure flag. The cookie might then wrongfully be\nsent over plaintext HTTP on subsequent requests to the same host.",
  "id": "GHSA-vmmm-3jqx-jgx8",
  "modified": "2026-09-08T21:33:03Z",
  "published": "2026-09-06T18:34:39Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-80255"
    },
    {
      "type": "WEB",
      "url": "https://hackerone.com/reports/3972395"
    },
    {
      "type": "WEB",
      "url": "https://curl.se/docs/CVE-2026-80255.html"
    },
    {
      "type": "WEB",
      "url": "https://curl.se/docs/CVE-2026-80255.json"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

MSRC_CVE-2026-80255

Vulnerability from csaf_microsoft - Published: 2026-09-08 01:04 - Updated: 2026-09-15 01:52

Summary

secure cookie attribute bypass with tab

Scope

1 vulnerability in this advisory, including CVE-2026-80255.

CVE-2026-80255

Known affected: 1 product Known not affected: 5 products

Open the full advisory

OPENSUSE-SU-2026:11696-1

Vulnerability from csaf_opensuse - Published: 2026-09-07 00:00 - Updated: 2026-09-17 17:23

Summary

curl-8.22.0-1.1 on GA media

Severity

Moderate

Scope

7 vulnerabilities in this advisory, including CVE-2026-80255.

CVE-2026-80255

3.1 (Low)


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

Recommended: 36 products

Open the full advisory

UBUNTU-CVE-2026-80255 (CVE-2026-80255)

Vulnerability from osv_ubuntu – Published: 2026-09-06 18:17 – Updated: 2026-09-16 11:41 – Source website

Details

Severity

7.5 (High)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-80255	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-80255	REPORT
	https://curl.se/docs/CVE-2026-80255.html	REPORT
	https://github.com/curl/curl/commit/4f6aa41a0145e…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "curl",
            "binary_version": "8.18.0-1ubuntu2.5"
          },
          {
            "binary_name": "libcurl3t64-gnutls",
            "binary_version": "8.18.0-1ubuntu2.5"
          },
          {
            "binary_name": "libcurl4t64",
            "binary_version": "8.18.0-1ubuntu2.5"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "curl",
        "purl": "pkg:deb/ubuntu/curl@8.18.0-1ubuntu2.5?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "8.14.1-2ubuntu1",
        "8.17.0-1ubuntu1",
        "8.18.0-1ubuntu1",
        "8.18.0-1ubuntu2",
        "8.18.0-1ubuntu2.1",
        "8.18.0-1ubuntu2.2",
        "8.18.0-1ubuntu2.3",
        "8.18.0-1ubuntu2.4",
        "8.18.0-1ubuntu2.5"
      ]
    }
  ],
  "aliases": [],
  "details": "A `Set-Cookie:` header using tab (horizontal tab, ASCII code 9) instead of space (ascii code 32) immediately before the `Secure` attribute causes curl to store the cookie without its Secure flag. The cookie might then wrongfully be sent over plaintext HTTP on subsequent requests to the same host.",
  "id": "UBUNTU-CVE-2026-80255",
  "modified": "2026-09-16T11:41:47Z",
  "published": "2026-09-06T18:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-80255"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-80255"
    },
    {
      "type": "REPORT",
      "url": "https://curl.se/docs/CVE-2026-80255.html"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/curl/curl/commit/4f6aa41a0145e930e76677"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-80255"
  ]
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2026-80255 (GCVE-0-2026-80255)

BELL-CVE-2026-80255 (CVE-2026-80255)

CERTFR-2026-AVI-1108

Solutions

FKIE_CVE-2026-80255

GHSA-VMMM-3JQX-JGX8

MSRC_CVE-2026-80255

OPENSUSE-SU-2026:11696-1

UBUNTU-CVE-2026-80255 (CVE-2026-80255)

Tags

Sightings

Nomenclature

Related by attack behaviour