Vulnerability-Lookup

ubuntu-cve-2026-77642

Vulnerability from osv_ubuntu

Published

2026-08-20 22:18

Modified

2026-09-10 09:05

Summary

Details

tor before 0.4.9.9 was prone to an out-of-bounds write when parsing a consensus or detached signature with unexpected signature digest type. Impact is minor for most Tor roles, but potentially major for directory authorities. This is TROVE-2026-019.

Severity

7.5 (High)


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

9.3 (Critical)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-77642	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-77642	REPORT
	https://gitlab.torproject.org/tpo/core/tor/-/work…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tor",
            "binary_version": "0.2.4.27-1ubuntu0.1+esm2"
          },
          {
            "binary_name": "tor-geoipdb",
            "binary_version": "0.2.4.27-1ubuntu0.1+esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "tor",
        "purl": "pkg:deb/ubuntu/tor@0.2.4.27-1ubuntu0.1+esm2?arch=source\u0026distro=esm-infra-legacy/trusty"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.2.3.25-1",
        "0.2.4.19-1",
        "0.2.4.20-1",
        "0.2.4.27-1build0.14.04.1",
        "0.2.4.27-1ubuntu0.1",
        "0.2.4.27-1ubuntu0.1+esm1",
        "0.2.4.27-1ubuntu0.1+esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tor",
            "binary_version": "0.2.9.14-1ubuntu1~16.04.3+esm1"
          },
          {
            "binary_name": "tor-geoipdb",
            "binary_version": "0.2.9.14-1ubuntu1~16.04.3+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "tor",
        "purl": "pkg:deb/ubuntu/tor@0.2.9.14-1ubuntu1~16.04.3+esm1?arch=source\u0026distro=esm-apps/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.2.6.10-1ubuntu2",
        "0.2.7.6-1ubuntu1",
        "0.2.9.11-1ubuntu1~16.04.1",
        "0.2.9.14-1ubuntu1~16.04.1",
        "0.2.9.14-1ubuntu1~16.04.2",
        "0.2.9.14-1ubuntu1~16.04.3",
        "0.2.9.14-1ubuntu1~16.04.3+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tor",
            "binary_version": "0.3.2.10-1ubuntu0.2~esm2"
          },
          {
            "binary_name": "tor-geoipdb",
            "binary_version": "0.3.2.10-1ubuntu0.2~esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "tor",
        "purl": "pkg:deb/ubuntu/tor@0.3.2.10-1ubuntu0.2~esm2?arch=source\u0026distro=esm-apps/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.3.0.10-1",
        "0.3.1.8-2",
        "0.3.1.9-1",
        "0.3.2.9-1",
        "0.3.2.9-1build1",
        "0.3.2.10-1",
        "0.3.2.10-1ubuntu0.1",
        "0.3.2.10-1ubuntu0.2~esm1",
        "0.3.2.10-1ubuntu0.2~esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tor",
            "binary_version": "0.4.2.7-1ubuntu0.1~esm1"
          },
          {
            "binary_name": "tor-geoipdb",
            "binary_version": "0.4.2.7-1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "tor",
        "purl": "pkg:deb/ubuntu/tor@0.4.2.7-1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.4.1.5-1",
        "0.4.1.5-1build1",
        "0.4.1.6-1",
        "0.4.2.5-1",
        "0.4.2.6-1",
        "0.4.2.7-1",
        "0.4.2.7-1ubuntu0.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tor",
            "binary_version": "0.4.9.11-0ubuntu0.22.04.1"
          },
          {
            "binary_name": "tor-geoipdb",
            "binary_version": "0.4.9.11-0ubuntu0.22.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "tor",
        "purl": "pkg:deb/ubuntu/tor@0.4.9.11-0ubuntu0.22.04.1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.4.5.9-1",
        "0.4.6.8-1",
        "0.4.6.8-1build1",
        "0.4.6.9-1",
        "0.4.6.10-1",
        "0.4.9.11-0ubuntu0.22.04.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tor",
            "binary_version": "0.4.9.11-0ubuntu0.24.04.1"
          },
          {
            "binary_name": "tor-geoipdb",
            "binary_version": "0.4.9.11-0ubuntu0.24.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "tor",
        "purl": "pkg:deb/ubuntu/tor@0.4.9.11-0ubuntu0.24.04.1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.4.8.4-2",
        "0.4.8.7-1",
        "0.4.8.9-1",
        "0.4.8.10-1",
        "0.4.8.10-1build1",
        "0.4.8.10-1build2",
        "0.4.9.11-0ubuntu0.24.04.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "tor",
            "binary_version": "0.4.9.11-0ubuntu0.26.04.1"
          },
          {
            "binary_name": "tor-geoipdb",
            "binary_version": "0.4.9.11-0ubuntu0.26.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "tor",
        "purl": "pkg:deb/ubuntu/tor@0.4.9.11-0ubuntu0.26.04.1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.4.8.16-1",
        "0.4.8.21-1",
        "0.4.8.22-1",
        "0.4.9.6-1",
        "0.4.9.11-0ubuntu0.26.04.1"
      ]
    }
  ],
  "aliases": [],
  "details": "tor before 0.4.9.9 was prone to an\u00a0out-of-bounds write when parsing a consensus or  detached signature with unexpected signature digest type. Impact  is minor for most Tor roles, but potentially major for directory authorities. This is TROVE-2026-019.",
  "id": "UBUNTU-CVE-2026-77642",
  "modified": "2026-09-10T09:05:17Z",
  "published": "2026-08-20T22:18:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-77642"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-77642"
    },
    {
      "type": "REPORT",
      "url": "https://gitlab.torproject.org/tpo/core/tor/-/work_items/41267"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-77642"
  ]
}

CVE-2026-77642 (GCVE-0-2026-77642)

Vulnerability from cvelistv5 – Published: 2026-08-20 21:15 – Updated: 2026-08-27 16:07

Summary

Severity

7.5 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-27 16:03 UTC

CWE

CWE-787 - Out-of-bounds Write

Assigner

mitre mitre root

References

1 reference

URL	Tags
https://gitlab.torproject.org/tpo/core/tor/-/raw/…

Impacted products

1 product

Vendor	Product	Version
torproject	Tor	Affected: 0.2.8.2-alpha , < 0.4.9.9 (custom) cpe:2.3:a:torproject:tor::::::::

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-77642",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-27T16:03:17.038602Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-27T16:07:03.716Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Tor",
          "vendor": "torproject",
          "versions": [
            {
              "lessThan": "0.4.9.9",
              "status": "affected",
              "version": "0.2.8.2-alpha",
              "versionType": "custom"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "0.4.9.9",
                  "versionStartIncluding": "0.2.8.2-alpha",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "tor before 0.4.9.9 was prone to an\u00a0out-of-bounds write when parsing a consensus or  detached signature with unexpected signature digest type. Impact  is minor for most Tor roles, but potentially major for directory   authorities. This is TROVE-2026-019."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H",
            "version": "3.1"
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          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
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      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-787",
              "description": "CWE-787 Out-of-bounds Write",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-20T21:15:49.660Z",
        "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
        "shortName": "mitre"
      },
      "references": [
        {
          "url": "https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.9/ChangeLog"
        }
      ],
      "x_generator": {
        "engine": "CVE-Request-form 0.0.1"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
    "assignerShortName": "mitre",
    "cveId": "CVE-2026-77642",
    "datePublished": "2026-08-20T21:15:49.660Z",
    "dateReserved": "2026-08-20T21:15:49.322Z",
    "dateUpdated": "2026-08-27T16:07:03.716Z",
    "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.

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.